Summa Th. I-II EN Qu.102 a.5

Whether there can be any suitable cause for the sacraments of the Old Law?


Objection: 1. It would seem that there can be no suitable cause for the sacraments of the Old Law. Because those things that are done for the purpose of divine worship should not be like the observances of idolaters: since it is written (
Dt 12,31): "Thou shalt not do in like manner to the Lord thy God: for they have done to their gods all the abominations which the Lord abhorreth." Now worshippers of idols used to knive themselves to the shedding of blood: for it is related (1R 18,28) that they "cut themselves after their manner with knives and lancets, till they were all covered with blood." For this reason the Lord commanded (Dt 14,1): "You shall not cut yourselves nor make any baldness for the dead." Therefore it was unfitting for circumcision to be prescribed by the Law (Lv 12,3).
2. Further, those things which are done for the worship of God should be marked with decorum and gravity; according to Ps 34,18: "I will praise Thee in a grave [Douay: 'strong'] people." But it seems to savor of levity for a man to eat with haste. Therefore it was unfittingly commanded (Ex 12,11) that they should eat the Paschal lamb "in haste." Other things too relative to the eating of the lamb were prescribed, which seem altogether unreasonable.
3. Further, the sacraments of the Old Law were figures of the sacraments of the New Law. Now the Paschal lamb signified the sacrament of the Eucharist, according to 1Co 5,7: "Christ our Pasch is sacrificed." Therefore there should also have been some sacraments of the Old Law to foreshadow the other sacraments of the New Law, such as Confirmation, Extreme Unction, and Matrimony, and so forth.
4. Further, purification can scarcely be done except by removing something impure. But as far as God is concerned, no bodily thing is reputed impure, because all bodies are God's creatures; and "every creature of God is good, and nothing to be rejected that is received with thanksgiving" (1Tm 4,4). It was therefore unfitting for them to be purified after contact with a corpse, or any similar corporeal infection.
5. Further, it is written (Si 34,4): "What can be made clean by the unclean?" But the ashes of the red heifer [*Cf. He 9,13] which was burnt, were unclean, since they made a man unclean: for it is stated (Nb 19,7, seqq.) that the priest who immolated her was rendered unclean "until the evening"; likewise he that burnt her; and he that gathered up her ashes. Therefore it was unfittingly prescribed there that the unclean should be purified by being sprinkled with those cinders.
6. Further, sins are not something corporeal that can be carried from one place to another: nor can man be cleansed from sin by means of something unclean. It was therefore unfitting for the purpose of expiating the sins of the people that the priest should confess the sins of the children of Israel on one of the buck-goats, that it might carry them away into the wilderness: while they were rendered unclean by the other, which they used for the purpose of purification, by burning it together with the calf outside the camp; so that they had to wash their clothes and their bodies with water (Lv 16).
7. Further, what is already cleansed should not be cleansed again. It was therefore unfitting to apply a second purification to a man cleansed from leprosy, or to a house; as laid down in Lv 14.
8. Further, spiritual uncleanness cannot be cleansed by material water or by shaving the hair. Therefore it seems unreasonable that the Lord ordered (Ex 30,18, seqq.) the making of a brazen laver with its foot, that the priests might wash their hands and feet before entering the temple; and that He commanded (Nb 8,7) the Levites to be sprinkled with the water of purification, and to shave all the hairs of their flesh.
9. Further, that which is greater cannot be cleansed by that which is less. Therefore it was unfitting that, in the Law, the higher and lower priests, as stated in Lv 8 [*Cf. Ex 29], and the Levites, according to Nb 8, should be consecrated with any bodily anointing, bodily sacrifices, and bodily oblations.
0. Further, as stated in 1S 16,7, "Man seeth those things that appear, but the Lord beholdeth the heart." But those things that appear outwardly in man are the dispositions of his body and his clothes. Therefore it was unfitting for certain special garments to be appointed to the higher and lower priests, as related in Ex 28 [*Cf. Lv 8,7, seqq.]. It seems, moreover, unreasonable that anyone should be debarred from the priesthood on account of defects in the body, as stated in Lv 21,17, seqq.: "Whosoever of thy seed throughout their families, hath a blemish, he shall not offer bread to his God . . . if he be blind, if he be lame," etc. It seems, therefore, that the sacraments of the Old Law were unreasonable.

On the contrary It is written (Lv 20,8): "I am the Lord that sanctify you." But nothing unreasonable is done by God, for it is written (Ps 103,24): "Thou hast made all things in wisdom." Therefore there was nothing without a reasonable cause in the sacraments of the Old Law, which were ordained to the sanctification of man.
I answer that As stated above (Question [101], Article [4]), the sacraments are, properly speaking, things applied to the worshippers of God for their consecration so as, in some way, to depute them to the worship of God. Now the worship of God belonged in a general way to the whole people; but in a special way, it belonged to the priests and Levites, who were the ministers of divine worship. Consequently, in these sacraments of the Old Law, certain things concerned the whole people in general; while others belonged to the ministers.In regard to both, three things were necessary. The first was to be established in the state of worshipping God: and this institution was brought about---for all in general, by circumcision, without which no one was admitted to any of the legal observances---and for the priests, by their consecration. The second thing required was the use of those things that pertain to divine worship. And thus, as to the people, there was the partaking of the paschal banquet, to which no uncircumcised man was admitted, as is clear from Ex 12,43, seqq.: and, as to the priests, the offering of the victims, and the eating of the loaves of proposition and of other things that were allotted to the use of the priests. The third thing required was the removal of all impediments to divine worship, viz. of uncleannesses. And then, as to the people, certain purifications were instituted for the removal of certain external uncleannesses; and also expiations from sins; while, as to the priests and Levites, the washing of hands and feet and the shaving of the hair were instituted.And all these things had reasonable causes, both literal, in so far as they were ordained to the worship of God for the time being, and figurative, in so far as they were ordained to foreshadow Christ: as we shall see by taking them one by one.

Reply to Objection: 1. The chief literal reason for circumcision was in order that man might profess his belief in one God. And because Abraham was the first to sever himself from the infidels, by going out from his house and kindred, for this reason he was the first to receive circumcision. This reason is set forth by the Apostle (Rm 4,9, seqq.) thus: "He received the sign of circumcision, a seal of the justice of the faith which he had, being uncircumcised"; because, to wit, we are told that "unto Abraham faith was reputed to justice," for the reason that "against hope he believed in hope," i.e. against the hope that is of nature he believed in the hope that is of grace, "that he might be made the father of many nations," when he was an old man, and his wife an old and barren woman. And in order that this declaration, and imitation of Abraham's faith, might be fixed firmly in the hearts of the Jews, they received in their flesh such a sign as they could not forget, wherefore it is written (Gn 17,13): "My covenant shall be in your flesh for a perpetual covenant." This was done on the eighth day, because until then a child is very tender, and so might be seriously injured; and is considered as something not yet consolidated: wherefore neither are animals offered before the eighth day. And it was not delayed after that time, lest some might refuse the sign of circumcision on account of the pain: and also lest the parents, whose love for their children increases as they become used to their presence and as they grow older, should withdraw their children from circumcision. A second reason may have been the weakening of concupiscence in that member. A third motive may have been to revile the worship of Venus and Priapus, which gave honor to that part of the body. The Lord's prohibition extended only to the cutting of oneself in honor of idols: and such was not the circumcision of which we have been speaking.The figurative reason for circumcision was that it foreshadowed the removal of corruption, which was to be brought about by Christ, and will be perfectly fulfilled in the eighth age, which is the age of those who rise from the dead. And since all corruption of guilt and punishment comes to us through our carnal origin, from the sin of our first parent, therefore circumcision was applied to the generative member. Hence the Apostle says (Col 2,11): "You are circumcised" in Christ "with circumcision not made by hand in despoiling of the body of the flesh, but in the circumcision of" Our Lord Jesus "Christ."
2. The literal reason of the paschal banquet was to commemorate the blessing of being led by God out of Egypt. Hence by celebrating this banquet they declared that they belonged to that people which God had taken to Himself out of Egypt. For when they were delivered from Egypt, they were commanded to sprinkle the lamb's blood on the transoms of their house doors, as though declaring that they were averse to the rites of the Egyptians who worshipped the ram. Wherefore they were delivered by the sprinkling or rubbing of the blood of the lamb on the door-posts, from the danger of extermination which threatened the Egyptians.Now two things are to be observed in their departure from Egypt: namely, their haste in going, for the Egyptians pressed them to go forth speedily, as related in Ex 12,33; and there was danger that anyone who did not hasten to go with the crowd might be slain by the Egyptians. Their haste was shown in two ways. First by what they ate. For they were commanded to eat unleavened bread, as a sign "that it could not be leavened, the Egyptians pressing them to depart"; and to eat roast meat, for this took less time to prepare; and that they should not break a bone thereof, because in their haste there was no time to break bones. Secondly, as to the manner of eating. For it is written: "You shall gird your reins, and you shall have shoes on your feet, holding staves in your hands, and you shall eat in haste": which clearly designates men at the point of starting on a journey. To this also is to be referred the command: "In one house shall it be eaten, neither shall you carry forth of the flesh thereof out of the house": because, to wit, on account of their haste, they could not send any gifts of it.The stress they suffered while in Egypt was denoted by the wild lettuces. The figurative reason is evident, because the sacrifice of the paschal lamb signified the sacrifice of Christ according to 1Co 5,7: "Christ our pasch is sacrificed." The blood of the lamb, which ensured deliverance from the destroyer, by being sprinkled on the transoms, signified faith in Christ's Passion, in the hearts and on the lips of the faithful, by which same Passion we are delivered from sin and death, according to 1P 1,18: "You were . . . redeemed . . . with the precious blood . . . of a lamb unspotted." The partaking of its flesh signified the eating of Christ's body in the Sacrament; and the flesh was roasted at the fire to signify Christ's Passion or charity. And it was eaten with unleavened bread to signify the blameless life of the faithful who partake of Christ's body, according to 1Co 5,8: "Let us feast . . . with the unleavened bread of sincerity and truth." The wild lettuces were added to denote repentance for sins, which is required of those who receive the body of Christ. Their loins were girt in sign of chastity: and the shoes of their feet are the examples of our dead ancestors. The staves they were to hold in their hands denoted pastoral authority: and it was commanded that the paschal lamb should be eaten in one house, i.e. in a catholic church, and not in the conventicles of heretics.
3. Some of the sacraments of the New Law had corresponding figurative sacraments in the Old Law. For Baptism, which is the sacrament of Faith, corresponds to circumcision. Hence it is written (Col 2,11-12): "You are circumcised . . . in the circumcision of" Our Lord Jesus "Christ: buried with Him in Baptism." In the New Law the sacrament of the Eucharist corresponds to the banquet of the paschal lamb. The sacrament of Penance in the New Law corresponds to all the purifications of the Old Law. The sacrament of Orders corresponds to the consecration of the pontiff and of the priests. To the sacrament of Confirmation, which is the sacrament of the fulness of grace, there would be no corresponding sacrament of the Old Law, because the time of fulness had not yet come, since "the Law brought no man [Vulg.: 'nothing'] to perfection" (He 7,19). The same applies to the sacrament of Extreme Unction, which is an immediate preparation for entrance into glory, to which the way was not yet opened out in the Old Law, since the price had not yet been paid. Matrimony did indeed exist under the Old Law, as a function of nature, but not as the sacrament of the union of Christ with the Church, for that union was not as yet brought about. Hence under the Old Law it was allowable to give a bill of divorce, which is contrary to the nature of the sacrament.
4. As already stated, the purifications of the Old Law were ordained for the removal of impediments to the divine worship: which worship is twofold; viz. spiritual, consisting in devotion of the mind to God; and corporal, consisting in sacrifices, oblations, and so forth. Now men are hindered in the spiritual worship by sins, whereby men were said to be polluted, for instance, by idolatry, murder, adultery, or incest. From such pollutions men were purified by certain sacrifices, offered either for the whole community in general, or also for the sins of individuals; not that those carnal sacrifices had of themselves the power of expiating sin; but that they signified that expiation of sins which was to be effected by Christ, and of which those of old became partakers by protesting their faith in the Redeemer, while taking part in the figurative sacrifices.The impediments to external worship consisted in certain bodily uncleannesses; which were considered in the first place as existing in man, and consequently in other animals also, and in man's clothes, dwelling-place, and vessels. In man himself uncleanness was considered as arising partly from himself and partly from contact with unclean things. Anything proceeding from man was reputed unclean that was already subject to corruption, or exposed thereto: and consequently since death is a kind of corruption, the human corpse was considered unclean. In like manner, since leprosy arises from corruption of the humors, which break out externally and infect other persons, therefore were lepers also considered unclean; and, again, women suffering from a flow of blood, whether from weakness, or from nature (either at the monthly course or at the time of conception); and, for the same reason, men were reputed unclean if they suffered from a flow of seed, whether due to weakness, to nocturnal pollution, or to sexual intercourse. Because every humor issuing from man in the aforesaid ways involves some unclean infection. Again, man contracted uncleanness by touching any unclean thing whatever.Now there was both a literal and a figurative reason for these uncleannesses. The literal reason was taken from the reverence due to those things that belong to the divine worship: both because men are not wont, when unclean, to touch precious things: and in order that by rarely approaching sacred things they might have greater respect for them. For since man could seldom avoid all the aforesaid uncleannesses, the result was that men could seldom approach to touch things belonging to the worship of God, so that when they did approach, they did so with greater reverence and humility. Moreover, in some of these the literal reason was that men should not be kept away from worshipping God through fear of coming in contact with lepers and others similarly afflicted with loathsome and contagious diseases. In others, again, the reason was to avoid idolatrous worship: because in their sacrificial rites the Gentiles sometimes employed human blood and seed. All these bodily uncleannesses were purified either by the mere sprinkling of water, or, in the case of those which were more grievous, by some sacrifice of expiation for the sin which was the occasion of the uncleanness in question.The figurative reason for these uncleannesses was that they were figures of various sins. For the uncleanness of any corpse signifies the uncleanness of sin, which is the death of the soul. The uncleanness of leprosy betokened the uncleanness of heretical doctrine: both because heretical doctrine is contagious just as leprosy is, and because no doctrine is so false as not to have some truth mingled with error, just as on the surface of a leprous body one may distinguish the healthy parts from those that are infected. The uncleanness of a woman suffering from a flow of blood denotes the uncleanness of idolatry, on account of the blood which is offered up. The uncleanness of the man who has suffered seminal loss signifies the uncleanness of empty words, for "the seed is the word of God." The uncleanness of sexual intercourse and of the woman in child-birth signifies the uncleanness of original sin. The uncleanness of the woman in her periods signifies the uncleanness of a mind that is sensualized by pleasure. Speaking generally, the uncleanness contracted by touching an unclean thing denotes the uncleanness arising from consent in another's sin, according to 2Co 6,17: "Go out from among them, and be ye separate . . . and touch not the unclean thing."Moreover, this uncleanness arising from the touch was contracted even by inanimate objects; for whatever was touched in any way by an unclean man, became itself unclean. Wherein the Law attenuated the superstition of the Gentiles, who held that uncleanness was contracted not only by touch, but also by speech or looks, as Rabbi Moses states (Doct. Perplex. iii) of a woman in her periods. The mystical sense of this was that "to God the wicked and his wickedness are hateful alike" (Sg 14,9).There was also an uncleanness of inanimate things considered in themselves, such as the uncleanness of leprosy in a house or in clothes. For just as leprosy occurs in men through a corrupt humor causing putrefaction and corruption in the flesh; so, too, through some corruption and excess of humidity or dryness, there arises sometimes a kind of corruption in the stones with which a house is built, or in clothes. Hence the Law called this corruption by the name of leprosy, whereby a house or a garment was deemed to be unclean: both because all corruption savored of uncleanness, as stated above, and because the Gentiles worshipped their household gods as a preservative against this corruption. Hence the Law prescribed such houses, where this kind of corruption was of a lasting nature, to be destroyed; and such garments to be burnt, in order to avoid all occasion of idolatry. There was also an uncleanness of vessels, of which it is written (Nb 19,15): "The vessel that hath no cover, and binding over it, shall be unclean." The cause of this uncleanness was that anything unclean might easily drop into such vessels, so as to render them unclean. Moreover, this command aimed at the prevention of idolatry. For idolaters believed that if mice, lizards, or the like, which they used to sacrifice to the idols, fell into the vessels or into the water, these became more pleasing to the gods. Even now some women let down uncovered vessels in honor of the nocturnal deities which they call "Janae."The figurative reason of these uncleannesses is that the leprosy of a house signified the uncleanness of the assembly of heretics; the leprosy of a linen garment signified an evil life arising from bitterness of mind; the leprosy of a woolen garment denoted the wickedness of flatterers; leprosy in the warp signified the vices of the soul; leprosy on the woof denoted sins of the flesh, for as the warp is in the woof, so is the soul in the body. The vessel that has neither cover nor binding, betokens a man who lacks the veil of taciturnity, and who is unrestrained by any severity of discipline.
5. As stated above (ad 4), there was a twofold uncleanness in the Law; one by way of corruption in the mind or in the body; and this was the graver uncleanness; the other was by mere contact with an unclean thing, and this was less grave, and was more easily expiated. Because the former uncleanness was expiated by sacrifices for sins, since all corruption is due to sin, and signifies sin: whereas the latter uncleanness was expiated by the mere sprinkling of a certain water, of which water we read in Nb 19. For there God commanded them to take a red cow in memory of the sin they had committed in worshipping a calf. And a cow is mentioned rather than a calf, because it was thus that the Lord was wont to designate the synagogue, according to Os 4,16: "Israel hath gone astray like a wanton heifer": and this was, perhaps, because they worshipped heifers after the custom of Egypt, according to Os 10,5: "(They) have worshipped the kine of Bethaven." And in detestation of the sin of idolatry it was sacrificed outside the camp; in fact, whenever sacrifice was offered up in expiation of the multitude of sins, it was all burnt outside the camp. Moreover, in order to show that this sacrifice cleansed the people from all their sins, "the priest" dipped "his finger in her blood," and sprinkled "it over against the door of the tabernacle seven times"; for the number seven signified universality. Further, the very sprinkling of blood pertained to the detestation of idolatry, in which the blood that was offered up was not poured out, but was collected together, and men gathered round it to eat in honor of the idols. Likewise it was burnt by fire, either because God appeared to Moses in a fire, and the Law was given from the midst of fire; or to denote that idolatry, together with all that was connected therewith, was to be extirpated altogether; just as the cow was burnt "with her skin and her flesh, her blood and dung being delivered to the flames." To this burning were added "cedar-wood, and hyssop, and scarlet twice dyed," to signify that just as cedar-wood is not liable to putrefaction, and scarlet twice dyed does not easily lose its color, and hyssop retains its odor after it has been dried; so also was this sacrifice for the preservation of the whole people, and for their good behavior and devotion. Hence it is said of the ashes of the cow: "That they may be reserved for the multitude of the children of Israel." Or, according to Josephus (Antiq. iii, 8,9,10), the four elements are indicated here: for "cedar-wood" was added to the fire, to signify the earth, on account of its earthiness; "hyssop," to signify the air, on account of its smell; "scarlet twice dyed," to signify water, for the same reason as purple, on account of the dyes which are taken out of the water: thus denoting the fact that this sacrifice was offered to the Creator of the four elements. And since this sacrifice was offered for the sin of idolatry, both "he that burned her," and "he that gathered up the ashes," and "he that sprinkled the water" in which the ashes were placed, were deemed unclean in detestation of that sin, in order to show that whatever was in any way connected with idolatry should be cast aside as being unclean. From this uncleanness they were purified by the mere washing of their clothes; nor did they need to be sprinkled with the water on account of this kind of uncleanness, because otherwise the process would have been unending, since he that sprinkled the water became unclean, so that if he were to sprinkle himself he would remain unclean; and if another were to sprinkle him, that one would have become unclean, and in like manner, whoever might sprinkle him, and so on indefinitely.The figurative reason of this sacrifice was that the red cow signified Christ in respect his assumed weakness, denoted by the female sex; while the color of the cow designated the blood of His Passion. And the "red cow was of full age," because all Christ's works are perfect, "in which there" was "no blemish"; "and which" had "not carried the yoke," because Christ was innocent, nor did He carry the yoke of sin. It was commanded to be taken to Moses, because they blamed Him for transgressing the law of Moses by breaking the Sabbath. And it was commanded to be delivered "to Eleazar the priest," because Christ was delivered into the hands of the priests to be slain. It was immolated "without the camp," because Christ "suffered outside the gate" (He 13,12). And the priest dipped "his finger in her blood," because the mystery of Christ's Passion should be considered and imitated.It was sprinkled "over against . . . the tabernacle," which denotes the synagogue, to signify either the condemnation of the unbelieving Jews, or the purification of believers; and this "seven times," in token either of the seven gifts of the Holy Ghost, or of the seven days wherein all time is comprised. Again, all things that pertain to the Incarnation of Christ should be burnt with fire, i.e. they should be understood spiritually; for the "skin" and "flesh" signified Christ's outward works; the "blood" denoted the subtle inward force which quickened His external deeds; the "dung" betokened His weariness, His thirst, and all such like things pertaining to His weakness. Three things were added, viz. "cedar-wood," which denotes the height of hope or contemplation; "hyssop," in token of humility or faith; "scarlet twice dyed," which denotes twofold charity; for it is by these three that we should cling to Christ suffering. The ashes of this burning were gathered by "a man that is clean," because the relics of the Passion came into the possession of the Gentiles, who were not guilty of Christ's death. The ashes were put into water for the purpose of expiation, because Baptism receives from Christ's Passion the power of washing away sins. The priest who immolated and burned the cow, and he who burned, and he who gathered together the ashes, were unclean, as also he that sprinkled the water: either because the Jews became unclean through putting Christ to death, whereby our sins are expiated; and this, until the evening, i.e. until the end of the world, when the remnants of Israel will be converted; or else because they who handle sacred things with a view to the cleansing of others contract certain uncleannesses, as Gregory says (Pastor. ii, 5); and this until the evening, i.e. until the end of this life.
6. As stated above (ad 5), an uncleanness which was caused by corruption either of mind or of body was expiated by sin-offerings. Now special sacrifices were wont to be offered for the sins of individuals: but since some were neglectful about expiating such sins and uncleannesses; or, through ignorance, failed to offer this expiation; it was laid down that once a year, on the tenth day of the seventh month, a sacrifice of expiation should be offered for the whole people. And because, as the Apostle says (He 7,28), "the Law maketh men priests, who have infirmity," it behooved the priest first of all to offer a calf for his own sins, in memory of Aaron's sin in fashioning the molten calf; and besides, to offer a ram for a holocaust, which signified that the priestly sovereignty denoted by the ram, who is the head of the flock, was to be ordained to the glory of God. Then he offered two he-goats for the people: one of which was offered in expiation of the sins of the multitude. For the he-goat is an evil-smelling animal; and from its skin clothes are made having a pungent odor; to signify the stench, uncleanness and the sting of sin. After this he-goat had been immolated, its blood was taken, together with the blood of the calf, into the Holy of Holies, and the entire sanctuary was sprinkled with it; to signify that the tabernacle was cleansed from the uncleanness of the children of Israel. But the corpses of the he-goat and calf which had been offered up for sin had to be burnt, to denote the destruction of sins. They were not, however, burnt on the altar: since none but holocausts were burnt thereon; but it was prescribed that they should be burnt without the camp, in detestation of sin: for this was done whenever sacrifice was offered for a grievous sin, or for the multitude of sins. The other goat was let loose into the wilderness: not indeed to offer it to the demons, whom the Gentiles worshipped in desert places, because it was unlawful to offer aught to them; but in order to point out the effect of the sacrifice which had been offered up. Hence the priest put his hand on its head, while confessing the sins of the children of Israel: as though that goat were to carry them away into the wilderness, where it would be devoured by wild beasts, because it bore the punishment of the people's sins. And it was said to bear the sins of the people, either because the forgiveness of the people's sins was signified by its being let loose, or because on its head written lists of sins were fastened.The figurative reason of these things was that Christ was foreshadowed both by the calf, on account of His power; and by the ram, because He is the Head of the faithful; and by the he-goat, on account of "the likeness of sinful flesh" (Rm 8,3). Moreover, Christ was sacrificed for the sins of both priests and people: since both those of high and those of low degree are cleansed from sin by His Passion. The blood of the calf and of the goat was brought into the Holies by the priest, because the entrance to the kingdom of heaven was opened to us by the blood of Christ's Passion. Their bodies were burnt without the camp, because "Christ suffered without the gate," as the Apostle declares (He 13,12). The scape-goat may denote either Christ's Godhead Which went away into solitude when the Man Christ suffered, not by going to another place, but by restraining His power: or it may signify the base concupiscence which we ought to cast away from ourselves, while we offer up to Our Lord acts of virtue.With regard to the uncleanness contracted by those who burnt these sacrifices, the reason is the same as that which we assigned (ad 5) to the sacrifice of the red heifer.
7. The legal rite did not cleanse the leper of his deformity, but declared him to be cleansed. This is shown by the words of Lv 14,3, seqq., where it was said that the priest, "when he shall find that the leprosy is cleansed," shall command "him that is to be purified": consequently, the leper was already healed: but he was said to be purified in so far as the verdict of the priest restored him to the society of men and to the worship of God. It happened sometimes, however, that bodily leprosy was miraculously cured by the legal rite, when the priest erred in his judgment.Now this purification of a leper was twofold: for, in the first place, he was declared to be clean; and, secondly, he was restored, as clean, to the society of men and to the worship of God, to wit, after seven days. At the first purification the leper who sought to be cleansed offered for himself "two living sparrows . . . cedar-wood, and scarlet, and hyssop," in such wise that a sparrow and the hyssop should be tied to the cedar-wood with a scarlet thread, so that the cedar-wood was like the handle of an aspersory: while the hyssop and sparrow were that part of the aspersory which was dipped into the blood of the other sparrow which was "immolated . . . over living waters." These things he offered as an antidote to the four defects of leprosy: for cedar-wood, which is not subject to putrefaction, was offered against the putrefaction; hyssop, which is a sweet-smelling herb, was offered up against the stench; a living sparrow was offered up against numbness; and scarlet, which has a vivid color, was offered up against the repulsive color of leprosy. The living sparrow was let loose to fly away into the plain, because the leper was restored to his former liberty.On the eighth day he was admitted to divine worship, and was restored to the society of men; but only after having shaved all the hair of his body, and washed his clothes, because leprosy rots the hair, infects the clothes, and gives them an evil smell. Afterwards a sacrifice was offered for his sin, since leprosy was frequently a result of sin: and some of the blood of the sacrifice was put on the tip of the ear of the man that was to be cleansed, "and on the thumb of his right hand, and the great toe of his right foot"; because it is in these parts that leprosy is first diagnosed and felt. In this rite, moreover, three liquids were employed: viz. blood, against the corruption of the blood; oil, to denote the healing of the disease; and living waters, to wash away the filth.The figurative reason was that the Divine and human natures in Christ were denoted by the two sparrows, one of which, in likeness of His human nature, was offered up in an earthen vessel over living waters, because the waters of Baptism are sanctified by Christ's Passion. The other sparrow, in token of His impassible Godhead, remained living, because the Godhead cannot die: hence it flew away, for the Godhead could not be encompassed by the Passion. Now this living sparrow, together with the cedar-wood and scarlet or cochineal, and hyssop, i.e. faith, hope and charity, as stated above (ad 5), was put into the water for the purpose of sprinkling, because we are baptized in the faith of the God-Man. By the waters of Baptism or of his tears man washes his clothes, i.e. his works, and all his hair, i.e. his thoughts. The tip of the right ear of the man to be cleansed is moistened with some the blood and oil, in order to strengthen his hearing against harmful words; and the thumb and toe of his right hand and foot are moistened that his deeds may be holy. Other matters pertaining to this purification, or to that also of any other uncleannesses, call for no special remark, beyond what applies to other sacrifices, whether for sins or for trespasses.
8. 9. Just as the people were initiated by circumcision to the divine worship, so were the ministers by some special purification or consecration: wherefore they are commanded to be separated from other men, as being specially deputed, rather than others, to the ministry of the divine worship. And all that was done touching them in their consecration or institution, was with a view to show that they were in possession of a prerogative of purity, power and dignity. Hence three things were done in the institution of ministers: for first, they were purified; secondly, they were adorned [*'Ornabantur.' Some editions have 'ordinabantur'---'were ordained': the former reading is a reference to Lv 8,7-9] and consecrated; thirdly, they were employed in the ministry. All in general used to be purified by washing in water, and by certain sacrifices; but the Levites in particular shaved all the hair of their bodies, as stated in Lv 8 (cf. Nb 8).With regard to the high-priests and priests the consecration was performed as follows. First, when they had been washed, they were clothed with certain special garments in designation of their dignity. In particular, the high-priest was anointed on the head with the oil of unction: to denote that the power of consecration was poured forth by him on to others, just as oil flows from the head on to the lower parts of the body; according to Ps 132,2: "Like the precious ointment on the head that ran down upon the beard, the beard of Aaron." But the Levites received no other consecration besides being offered to the Lord by the children of Israel through the hands of the high-priest, who prayed for them. The lesser priests were consecrated on the hands only, which were to be employed in the sacrifices. The tip of their right ear and the thumb of their right hand, and the great toe of their right foot were tinged with the blood of the sacrificial animal, to denote that they should be obedient to God's law in offering the sacrifices (this is denoted by touching their right ear); and that they should be careful and ready in performing the sacrifices (this is signified by the moistening of the right foot and hand). They themselves and their garments were sprinkled with the blood of the animal that had been sacrificed, in memory of the blood of the lamb by which they had been delivered in Egypt. At their consecration the following sacrifices were offered: a calf, for sin, in memory of Aaron's sin in fashioning the molten calf; a ram, for a holocaust, in memory of the sacrifice of Abraham, whose obedience it behooved the high-priest to imitate; again, a ram of consecration, which was a peace-offering, in memory of the delivery form Egypt through the blood of the lamb; and a basket of bread, in memory of the manna vouchsafed to the people.In reference to their being destined to the ministry, the fat of the ram, one roll of bread, and the right shoulder were placed on their hands, to show that they received the power of offering these things to the Lord: while the Levites were initiated to the ministry by being brought into the tabernacle of the covenant, as being destined to the ministry touching the vessels of the sanctuary.The figurative reason of these things was that those who are to be consecrated to the spiritual ministry of Christ, should be first of all purified by the waters of Baptism, and by the waters of tears, in their faith in Christ's Passion, which is a sacrifice both of expiation and of purification. They have also to shave all the hair of their body, i.e. all evil thoughts. They should, moreover, be decked with virtues, and be consecrated with the oil of the Holy Ghost, and with the sprinkling of Christ's blood. And thus they should be intent on the fulfilment of their spiritual ministry.
0. As already stated (Article [4]), the purpose of the Law was to induce men to have reverence for the divine worship: and this in two ways; first, by excluding from the worship of God whatever might be an object of contempt; secondly, by introducing into the divine worship all that seemed to savor of reverence. And, indeed, if this was observed in regard to the tabernacle and its vessels, and in the animals to be sacrificed, much more was it to be observed in the very ministers. Wherefore, in order to obviate contempt for the ministers, it was prescribed that they should have no bodily stain or defect: since men so deformed are wont to be despised by others. For the same reason it was also commanded that the choice of those who were to be destined to the service of God was not to be made in a broadcast manner from any family, but according to their descent from one particular stock, thus giving them distinction and nobility.In order that they might be revered, special ornate vestments were appointed for their use, and a special form of consecration. This indeed is the general reason of ornate garments. But the high-priest in particular had eight vestments. First, he had a linen tunic. Secondly, he had a purple tunic; round the bottom of which were placed "little bells" and "pomegranates of violet, and purple, and scarlet twice dyed." Thirdly, he had the ephod, which covered his shoulders and his breast down to the girdle; and it was made of gold, and violet and purple, and scarlet twice dyed and twisted linen: and on his shoulders he bore two onyx stones, on which were graven the names of the children of Israel. Fourthly, he had the rational, made of the same material; it was square in shape, and was worn on the breast, and was fastened to the ephod. On this rational there were twelve precious stones set in four rows, on which also were graven the names of the children of Israel, in token that the priest bore the burden of the whole people, since he bore their names on his shoulders; and that it was his duty ever to think of their welfare, since he wore them on his breast, bearing them in his heart, so to speak. And the Lord commanded the "Doctrine and Truth" to be put in the rational: for certain matters regarding moral and dogmatic truth were written on it. The Jews indeed pretend that on the rational was placed a stone which changed color according to the various things which were about to happen to the children of Israel: and this they call the "Truth and Doctrine." Fifthly, he wore a belt or girdle made of the four colors mentioned above. Sixthly, there was the tiara or mitre which was made of linen. Seventhly, there was the golden plate which hung over his forehead; on it was inscribed the Lord's name. Eighthly, there were "the linen breeches to cover the flesh of their nakedness," when they went up to the sanctuary or altar. Of these eight vestments the lesser priests had four, viz. the linen tunic and breeches, the belt and the tiara.According to some, the literal reason for these vestments was that they denoted the disposition of the terrestrial globe; as though the high-priest confessed himself to be the minister of the Creator of the world, wherefore it is written (Sg 18,24): "In the robe" of Aaron "was the whole world" described. For the linen breeches signified the earth out of which the flax grows. The surrounding belt signified the ocean which surrounds the earth. The violet tunic denoted the air by its color: its little bells betoken the thunder; the pomegranates, the lightning. The ephod, by its many colors, signified the starry heaven; the two onyx stones denoted the two hemispheres, or the sun and moon. The twelve precious stones on the breast are the twelve signs of the zodiac: and they are said to have been placed on the rational because in heaven, are the types [rationes] of earthly things, according to Jb 38,33: "Dost thou know the order of heaven, and canst thou set down the reason [rationem] thereof on the earth?" The turban or tiara signified the empyrean: the golden plate was a token of God, the governor of the universe.The figurative reason is evident. Because bodily stains or defects wherefrom the priests had to be immune, signify the various vices and sins from which they should be free. Thus it is forbidden that he should be blind, i.e. he ought not to be ignorant: he must not be lame, i.e. vacillating and uncertain of purpose: that he must have "a little, or a great, or a crooked nose," i.e. that he should not, from lack of discretion, exceed in one direction or in another, or even exercise some base occupation: for the nose signifies discretion, because it discerns odors. It is forbidden that he should have "a broken foot" or "hand," i.e. he should not lose the power of doing good works or of advancing in virtue. He is rejected, too, if he have a swelling either in front or behind [Vulg.: 'if he be crook-backed']: by which is signified too much love of earthly things: if he be blear-eyed, i.e. if his mind is darkened by carnal affections: for running of the eyes is caused by a flow of matter. He is also rejected if he had "a pearl in his eye," i.e. if he presumes in his own estimation that he is clothed in the white robe of righteousness. Again, he is rejected "if he have a continued scab," i.e. lustfulness of the flesh: also, if he have "a dry scurf," which covers the body without giving pain, and is a blemish on the comeliness of the members; which denotes avarice. Lastly, he is rejected "if he have a rupture" or hernia; through baseness rending his heart, though it appear not in his deeds.The vestments denote the virtues of God's ministers. Now there are four things that are necessary to all His ministers, viz. chastity denoted by the breeches; a pure life, signified by the linen tunic; the moderation of discretion, betokened by the girdle; and rectitude of purpose, denoted by the mitre covering the head. But the high-priests needed four other things in addition to these. First, a continual recollection of God in their thoughts; and this was signified by the golden plate worn over the forehead, with the name of God engraved thereon. Secondly, they had to bear with the shortcomings of the people: this was denoted by the ephod which they bore on their shoulders. Thirdly, they had to carry the people in their mind and heart by the solicitude of charity, in token of which they wore the rational. Fourthly, they had to lead a godly life by performing works of perfection; and this was signified by the violet tunic. Hence little golden bells were fixed to the bottom of the violet tunic, which bells signified the teaching of divine things united in the high-priest to his godly mode of life. In addition to these were the pomegranates, signifying unity of faith and concord in good morals: because his doctrine should hold together in such a way that it should not rend asunder the unity of faith and peace.

Summa Th. I-II EN Qu.102 a.5