Summa Th. II-II EN Qu.83 a.12

Whether prayer should be vocal?

Objection: 1. It would seem that prayer ought not to be vocal. As stated above (Article [4]), prayer is addressed chiefly to God. Now God knows the language of the heart. Therefore it is useless to employ vocal prayer.
2. Further, prayer should lift man's mind to God, as stated above (Article [1], ad 2). But words, like other sensible objects, prevent man from ascending to God by contemplation. Therefore we should not use words in our prayers.
3. Further, prayer should be offered to God in secret, according to Mt 6,6, "But thou, when thou shalt pray, enter into thy chamber, and having shut the door, pray to thy Father in secret." But prayer loses its secrecy by being expressed vocally. Therefore prayer should not be vocal.

On the contrary It is written (Ps 141,2): "I cried to the Lord with my voice, with my voice I made supplication to the Lord."
I answer that Prayer is twofold, common and individual. Common prayer is that which is offered to God by the ministers of the Church representing the body of the faithful: wherefore such like prayer should come to the knowledge of the whole people for whom it is offered: and this would not be possible unless it were vocal prayer. Therefore it is reasonably ordained that the ministers of the Church should say these prayers even in a loud voice, so that they may come to the knowledge of all.On the other hand individual prayer is that which is offered by any single person, whether he pray for himself or for others; and it is not essential to such a prayer as this that it be vocal. And yet the voice is employed in such like prayers for three reasons. First, in order to excite interior devotion, whereby the mind of the person praying is raised to God, because by means of external signs, whether of words or of deeds, the human mind is moved as regards apprehension, and consequently also as regards the affections. Hence Augustine says (ad Probam. Ep. cxxx, 9) that "by means of words and other signs we arouse ourselves more effectively to an increase of holy desires." Hence then alone should we use words and such like signs when they help to excite the mind internally. But if they distract or in any way impede the mind we should abstain from them; and this happens chiefly to those whose mind is sufficiently prepared for devotion without having recourse to those signs. Wherefore the Psalmist (Ps 26,8) said: "My heart hath said to Thee: 'My face hath sought Thee,'" and we read of Anna (1R 1,13) that "she spoke in her heart." Secondly, the voice is used in praying as though to pay a debt, so that man may serve God with all that he has from God, that is to say, not only with his mind, but also with his body: and this applies to prayer considered especially as satisfactory. Hence it is written (Os 14,3): "Take away all iniquity, and receive the good: and we will render the calves of our lips." Thirdly, we have recourse to vocal prayer, through a certain overflow from the soul into the body, through excess of feeling, according to Ps 15,9, "My heart hath been glad, and my tongue hath rejoiced."

Reply to Objection: 1. Vocal prayer is employed, not in order to tell God something He does not know, but in order to lift up the mind of the person praying or of other persons to God.
2. Words about other matters distract the mind and hinder the devotion of those who pray: but words signifying some object of devotion lift up the mind, especially one that is less devout.
3. As Chrysostom says [*Hom. xiii in the Opus Imperfectum falsely ascribed to St. John Chrysostom], "Our Lord forbids one to pray in presence of others in order that one may be seen by others. Hence when you pray, do nothing strange to draw men's attention, either by shouting so as to be heard by others, or by openly striking the heart, or extending the hands, so as to be seen by many. And yet, "according to Augustine (De Serm. Dom. in Monte ii, 3), "it is not wrong to be seen by men, but to do this or that in order to be seen by men."

Whether attention is a necessary condition of prayer?

Objection: 1. It would seem that attention is a necessary condition of prayer. It is written (Jn 4,24): "God is a spirit, and they that adore Him must adore Him in spirit and in truth." But prayer is not in spirit unless it be attentive. Therefore attention is a necessary condition of prayer.
2. Further, prayer is "the ascent of the mind to God" [*Damascene, De Fide Orth. iii, 24]. But the mind does not ascend to God if the prayer is inattentive. Therefore attention is a necessary condition of prayer.
3. Further, it is a necessary condition of prayer that it should be altogether sinless. Now if a man allows his mind to wander while praying he is not free of sin, for he seems to make light of God; even as if he were to speak to another man without attending to what he was saying. Hence Basil says [*De Constit. Monach. i] that the "Divine assistance is to be implored, not lightly, nor with a mind wandering hither and thither: because he that prays thus not only will not obtain what he asks, nay rather will he provoke God to anger." Therefore it would seem a necessary condition of prayer that it should be attentive.

On the contrary Even holy men sometimes suffer from a wandering of the mind when they pray, according to Ps 39,13, "My heart hath forsaken me."
I answer that This question applies chiefly to vocal prayer. Accordingly we must observe that a thing is necessary in two ways. First, a thing is necessary because thereby the end is better obtained: and thus attention is absolutely necessary for prayer. Secondly, a thing is said to be necessary when without it something cannot obtain its effect. Now the effect of prayer is threefold. The first is an effect which is common to all acts quickened by charity, and this is merit. In order to realize this effect, it is not necessary that prayer should be attentive throughout; because the force of the original intention with which one sets about praying renders the whole prayer meritorious, as is the case with other meritorious acts. The second effect of prayer is proper thereto, and consists in impetration: and again the original intention, to which God looks chiefly, suffices to obtain this effect. But if the original intention is lacking, prayer lacks both merit and impetration: because, as Gregory [*Hugh St. Victor, Expos. in Reg. S. Aug. iii] says, "God hears not the prayer of those who pay no attention to their prayer." The third effect of prayer is that which it produces at once; this is the spiritual refreshment of the mind, and for this effect attention is a necessary condition: wherefore it is written (1Co 14,14): "If I pray in a tongue . . . my understanding is without fruit."It must be observed, however, that there are three kinds of attention that can be brought to vocal prayer: one which attends to the words, lest we say them wrong, another which attends to the sense of the words, and a third, which attends to the end of prayer, namely, God, and to the thing we are praying for. That last kind of attention is most necessary, and even idiots are capable of it. Moreover this attention, whereby the mind is fixed on God, is sometimes so strong that the mind forgets all other things, as Hugh of St. Victor states [*De Modo Orandi ii].

Reply to Objection: 1. To pray in spirit and in truth is to set about praying through the instigation of the Spirit, even though afterwards the mind wander through weakness.
2. The human mind is unable to remain aloft for long on account of the weakness of nature, because human weakness weighs down the soul to the level of inferior things: and hence it is that when, while praying, the mind ascends to God by contemplation, of a sudden it wanders off through weakness.
3. Purposely to allow one's mind to wander in prayer is sinful and hinders the prayer from having fruit. It is against this that Augustine says in his Rule (Ep. ccxi): "When you pray God with psalms and hymns, let your mind attend to that which your lips pronounce." But to wander in mind unintentionally does not deprive prayer of its fruit. Hence Basil says (De Constit. Monach. i): "If you are so truly weakened by sin that you are unable to pray attentively, strive as much as you can to curb yourself, and God will pardon you, seeing that you are unable to stand in His presence in a becoming manner, not through negligence but through frailty."

Whether prayer should last a long time?

Objection: 1. It would seem that prayer should not be continual. It is written (Mt 6,7): "When you are praying, speak not much." Now one who prays a long time needs to speak much, especially if his be vocal prayer. Therefore prayer should not last a long time.
2. Further, prayer expresses the desire. Now a desire is all the holier according as it is centered on one thing, according to Ps 26,4, "One thing I have asked of the Lord, this will I seek after." Therefore the shorter prayer is, the more is it acceptable to God.
3. Further, it seems to be wrong to transgress the limits fixed by God, especially in matters concerning Divine worship, according to Ex 19,21: "Charge the people, lest they should have a mind to pass the limits to see the Lord, and a very great multitude of them should perish." But God has fixed for us the limits of prayer by instituting the Lord's Prayer (Mt 6). Therefore it is not right to prolong our prayer beyond its limits.

On the contrary On the contrary, It would seem that we ought to pray continually. For our Lord said (Lc 18,1): "We ought always to pray, and not to faint": and it is written (1Th 5,17): "Pray without ceasing."
I answer that We may speak about prayer in two ways: first, by considering it in itself; secondly, by considering it in its cause. The not cause of prayer is the desire of charity, from which prayer ought to arise: and this desire ought to be in us continually, either actually or virtually, for the virtue of this desire remains in whatever we do out of charity; and we ought to "do all things to the glory of God" (1Co 10,31). From this point of view prayer ought to be continual: wherefore Augustine says (ad Probam, Ep. cxxx, 9): "Faith, hope and charity are by themselves a prayer of continual longing." But prayer, considered in itself, cannot be continual, because we have to be busy about other works, and, as Augustine says (ad Probam. Ep. cxxx, 9), "we pray to God with our lips at certain intervals and seasons, in order to admonish ourselves by means of such like signs, to take note of the amount of our progress in that desire, and to arouse ourselves more eagerly to an increase thereof." Now the quantity of a thing should be commensurate with its end, for instance the quantity of the dose should be commensurate with health. And so it is becoming that prayer should last long enough to arouse the fervor of the interior desire: and when it exceeds this measure, so that it cannot be continued any longer without causing weariness, it should be discontinued. Wherefore Augustine says (ad Probam. Ep. cxxx): "It is said that the brethren in Egypt make frequent but very short prayers, rapid ejaculations, as it were, lest that vigilant and erect attention which is so necessary in prayer slacken and languish, through the strain being prolonged. By so doing they make it sufficiently clear not only that this attention must not be forced if we are unable to keep it up, but also that if we are able to continue, it should not be broken off too soon." And just as we must judge of this in private prayers by considering the attention of the person praying, so too, in public prayers we must judge of it by considering the devotion of the people.

Reply to Objection: 1. As Augustine says (ad Probam. Ep. cxxx), "to pray with many words is not the same as to pray long; to speak long is one thing, to be devout long is another. For it is written that our Lord passed the whole night in prayer, and that He 'prayed the longer' in order to set us an example." Further on he says: "When praying say little, yet pray much so long as your attention is fervent. For to say much in prayer is to discuss your need in too many words: whereas to pray much is to knock at the door of Him we pray, by the continuous and devout clamor of the heart. Indeed this business is frequently done with groans rather than with words, with tears rather than with speech."
2. Length of prayer consists, not in praying for many things, but in the affections persisting in the desire of one thing.
3. Our Lord instituted this prayer, not that we might use no other words when we pray, but that in our prayers we might have none but these things in view, no matter how we express them or think of them.
4. One may pray continually, either through having a continual desire, as stated above; or through praying at certain fixed times, though interruptedly; or by reason of the effect, whether in the person who prays---because he remains more devout even after praying, or in some other person---as when by his kindness a man incites another to pray for him, even after he himself has ceased praying.

Whether prayer is meritorious?

Objection: 1. It would seem that prayer is not meritorious. All merit proceeds from grace. But prayer precedes grace, since even grace is obtained by means of prayer according to Lc 11,13, "(How much more) will your Father from heaven give the good Spirit to them that ask Him!" Therefore prayer is not a meritorious act.
2. Further, if prayer merits anything, this would seem to be chiefly that which is besought in prayer. Yet it does not always merit this, because even the saints' prayers are frequently not heard; thus Paul was not heard when he besought the sting of the flesh to be removed from him. Therefore prayer is not a meritorious act.
3. Further, prayer is based chiefly on faith, according to Jc 1,6, "But let him ask in faith, nothing wavering." Now faith is not sufficient for merit, as instanced in those who have lifeless faith. Therefore prayer is not a meritorious act.

On the contrary A gloss on the words of Ps 34,13, "My prayer shall be turned into my bosom," explains them as meaning, "if my prayer does not profit them, yet shall not I be deprived of my reward." Now reward is not due save to merit. Therefore prayer is meritorious.
I answer that As stated above (Article [13]) prayer, besides causing spiritual consolation at the time of praying, has a twofold efficacy in respect of a future effect, namely, efficacy in meriting and efficacy in impetrating. Now prayer, like any other virtuous act, is efficacious in meriting, because it proceeds from charity as its root, the proper object of which is the eternal good that we merit to enjoy. Yet prayer proceeds from charity through the medium of religion, of which prayer is an act, as stated above (Article [3]), and with the concurrence of other virtues requisite for the goodness of prayer, viz. humility and faith. For the offering of prayer itself to God belongs to religion, while the desire for the thing. that we pray to be accomplished belongs to charity. Faith is necessary in reference to God to Whom we pray; that is, we need to believe that we can obtain from Him what we seek. Humility is necessary on the part of the person praying, because he recognizes his neediness. Devotion too is necessary: but this belongs to religion, for it is its first act and a necessary condition of all its secondary acts, as stated above (Question [82], Articles [1],2).As to its efficacy in impetrating, prayer derives this from the grace of God to Whom we pray, and Who instigates us to pray. Wherefore Augustine says (De Verb. Dom., Serm. cv, 1): "He would not urge us to ask, unless He were willing to give"; and Chrysostom [*Cf. Catena Aurea of St. Thomas on Lc 18. The words as quoted are not to be found in the words of Chrysostom] says: "He never refuses to grant our prayers, since in His loving-kindness He urged us not to faint in praying."

Reply to Objection: 1. Neither prayer nor any other virtuous act is meritorious without sanctifying grace. And yet even that prayer which impetrates sanctifying grace proceeds from some grace, as from a gratuitous gift, since the very act of praying is "a gift of God," as Augustine states (De Persever. xxiii).
2. Sometimes the merit of prayer regards chiefly something distinct from the object of one's petition. For the chief object of merit is beatitude, whereas the direct object of the petition of prayer extends sometimes to certain other things, as stated above (Articles [6],7). Accordingly if this other thing that we ask for ourselves be not useful for our beatitude, we do not merit it; and sometimes by asking for and desiring such things we lose merit for instance if we ask of God the accomplishment of some sin, which would be an impious prayer. And sometimes it is not necessary for salvation, nor yet manifestly contrary thereto; and then although he who prays may merit eternal life by praying, yet he does not merit to obtain what he asks for. Hence Augustine says (Liber. Sentent. Prosperi sent. ccxii): "He who faithfully prays God for the necessaries of this life, is both mercifully heard, and mercifully not heard. For the physician knows better than the sick man what is good for the disease." For this reason, too, Paul was not heard when he prayed for the removal of the sting in his flesh, because this was not expedient. If, however, we pray for something that is useful for our beatitude, through being conducive to salvation, we merit it not only by praying, but also by doing other good deeds: therefore without any doubt we receive what we ask for, yet when we ought to receive it: "since certain things are not denied us, but are deferred that they may be granted at a suitable time," according to Augustine (Tract. cii in Joan.): and again this may be hindered if we persevere not in asking for it. Wherefore Basil says (De Constit. Monast. i): "The reason why sometimes thou hast asked and not received, is because thou hast asked amiss, either inconsistently, or lightly, or because thou hast asked for what was not good for thee, or because thou hast ceased asking." Since, however, a man cannot condignly merit eternal life for another, as stated above (I-II 114,6), it follows that sometimes one cannot condignly merit for another things that pertain to eternal life. For this reason we are not always heard when we pray for others, as stated above (Article [7], ad 2,3). Hence it is that four conditions are laid down; namely, to ask---"for ourselves---things necessary for salvation---piously---perseveringly"; when all these four concur, we always obtain what we ask for.
3. Prayer depends chiefly on faith, not for its efficacy in meriting, because thus it depends chiefly on charity, but for its efficacy in impetrating, because it is through faith that man comes to know of God's omnipotence and mercy, which are the source whence prayer impetrates what it asks for.

Whether sinners impetrate anything from God by their prayers?

Objection: 1. It would seem that sinners impetrate nothing from God by their prayers. It is written (Jn 9,31): "We know that God doth not hear sinners"; and this agrees with the saying of Pr 28,9, "He that turneth away his ears from hearing the law, his prayer shall be an abomination." Now an abominable prayer impetrates nothing from God. Therefore sinners impetrate nothing from God.
2. Further, the just impetrate from God what they merit, as stated above (Article [15], ad 2). But sinners cannot merit anything since they lack grace and charity which is the "power of godliness," according to a gloss on 2Tm 3,5, "Having an appearance indeed of godliness, but denying the power thereof." and so their prayer is impious, and yet piety it required in order that prayer may be impetrative, as stated above (Article [15], ad 2). Therefore sinners impetrate nothing by their prayers.
3. Further, Chrysostom [*Hom. xiv in the Opus Imperfectum falsely ascribed to St. John Chrysostom] says: "The Father is unwilling to hear the prayer which the Son has not inspired." Now in the prayer inspired by Christ we say: "Forgive us our trespasses as we forgive them that trespass against us": and sinners do not fulfil this. Therefore either they lie in saying this, and so are unworthy to be heard, or, if they do not say it, they are not heard, because they do not observe the form of prayer instituted by Christ.

On the contrary Augustine says (Tract. xliv, super Joan.): "If God were not to hear sinners, the publican would have vainly said: Lord, be merciful to me a sinner"; and Chrysostom [*Hom. xviii of the same Opus Imperfectum] says: "Everyone that asketh shall receive, that is to say whether he be righteous or sinful."
I answer that In the sinner, two things are to be considered: his nature which God loves, and the sin which He hates. Accordingly when a sinner prays for something as sinner, i.e. in accordance with a sinful desire, God hears him not through mercy but sometimes through vengeance when He allows the sinner to fall yet deeper into sin. For "God refuses in mercy what He grants in anger," as Augustine declares (Tract. lxxiii in Joan.). On the other hand God hears the sinner's prayer if it proceed from a good natural desire, not out of justice, because the sinner does not merit to be heard, but out of pure mercy [*Cf. Article [15], ad 1], provided however he fulfil the four conditions given above, namely, that he beseech for himself things necessary for salvation, piously and perseveringly.

Reply to Objection: 1. As Augustine states (Tract. xliv super Joan.), these words were spoken by the blind man before being anointed, i.e. perfectly enlightened, and consequently lack authority. And yet there is truth in the saying if it refers to a sinner as such, in which sense also the sinner's prayer is said to be an abomination.
2. There can be no godliness in the sinner's prayer as though his prayer were quickened by a habit of virtue: and yet his prayer may be godly in so far as he asks for something pertaining to godliness. Even so a man who has not the habit of justice is able to will something just, as stated above (Question [59], Article [2]). And though his prayer is not meritorious, it can be impetrative, because merit depends on justice, whereas impetration rests on grace.
3. As stated above (Article [7], ad 1) the Lord's Prayer is pronounced in the common person of the whole Church: and so if anyone say the Lord's Prayer while unwilling to forgive his neighbor's trespasses, he lies not, although his words do not apply to him personally: for they are true as referred to the person of the Church, from which he is excluded by merit, and consequently he is deprived of the fruit of his prayer. Sometimes, however, a sinner is prepared to forgive those who have trespassed against him, wherefore his prayers are heard, according to Si 28,2, "Forgive thy neighbor if he hath hurt thee, and then shall thy sins be forgiven to thee when thou prayest."

Whether the parts of prayer are fittingly described as supplications, prayers, intercessions, and thanksgivings?

Objection: 1. It would seem that the parts of prayer are unfittingly described as supplications, prayers, intercessions, and thanksgivings. Supplication would seem to be a kind of adjuration. Yet, according to Origen (Super Matth. Tract. xxxv), "a man who wishes to live according to the gospel need not adjure another, for if it be unlawful to swear, it is also unlawful to adjure." Therefore supplication is unfittingly reckoned a part of prayer.
2. Further, according to Damascene (De Fide Orth. iii, 24), "to pray is to ask becoming things of God." Therefore it is unfitting to distinguish "prayers" from "intercessions."
3. Further, thanksgivings regard the past, while the others regard the future. But the past precedes the future. Therefore thanksgivings are unfittingly placed after the others.

On the contrary suffices the authority of the Apostle (1Tm 2,1).
I answer that Three conditions are requisite for prayer. First, that the person who prays should approach God Whom he prays: this is signified in the word "prayer," because prayer is "the raising up of one's mind to God." The second is that there should be a petition, and this is signified in the word "intercession." In this case sometimes one asks for something definite, and then some say it is "intercession" properly so called, or we may ask for some thing indefinitely, for instance to be helped by God, or we may simply indicate a fact, as in Jn 11,3, "Behold, he whom Thou lovest is sick," and then they call it "insinuation." The third condition is the reason for impetrating what we ask for: and this either on the part of God, or on the part of the person who asks. The reason of impetration on the part of God is His sanctity, on account of which we ask to be heard, according to Da 9,17-18, "For Thy own sake, incline, O God, Thy ear"; and to this pertains "supplication" [obsecratio] which means a pleading through sacred things, as when we say, "Through Thy nativity, deliver us, O Lord." The reason for impetration on the part of the person who asks is "thanksgiving"; since "through giving thanks for benefits received we merit to receive yet greater benefits," as we say in the collect [*Ember Friday in September and Postcommunion of the common of a Confessor Bishop]. Hence a gloss on 1Tm 2,1 says that "in the Mass, the consecration is preceded by supplication," in which certain sacred things are called to mind; that "prayers are in the consecration itself," in which especially the mind should be raised up to God; and that "intercessions are in the petitions that follow, and thanksgivings at the end."We may notice these four things in several of the Church's collects. Thus in the collect of Trinity Sunday the words, "Almighty eternal God" belong to the offering up of prayer to God; the words, "Who hast given to Thy servants," etc. belong to thanksgiving; the words, "grant, we beseech Thee," belong to intercession; and the words at the end, "Through Our Lord," etc. belong to supplication.In the "Conferences of the Fathers" (ix, cap. 11, seqq.) we read: "Supplication is bewailing one's sins; prayer is vowing something to God; intercession is praying for others; thanksgiving is offered by the mind to God in ineffable ecstasy." The first explanation, however, is the better.

Reply to Objection: 1. "Supplication" is an adjuration not for the purpose of compelling, for this is forbidden, but in order to implore mercy.
2. "Prayer" in the general sense includes all the things mentioned here; but when distinguished from the others it denotes properly the ascent to God.
3. Among things that are diverse the past precedes the future; but the one and same thing is future before it is past. Hence thanksgiving for other benefits precedes intercession: but one and the same benefit is first sought, and finally, when it has been received, we give thanks for it. Intercession is preceded by prayer whereby we approach Him of Whom we ask: and prayer is preceded by supplication, whereby through the consideration of God's goodness we dare approach Him.




In due sequence we must consider the external acts of latria, and in the first place, adoration whereby one uses one's body to reverence God; secondly, those acts whereby some external thing is offered to God; thirdly, those acts whereby something belonging to God is assumed.

Under the first head there are three points of inquiry:

(1) Whether adoration is an act of latria?

(2) Whether adoration denotes an internal or an external act?

(3) Whether adoration requires a definite place?

Whether adoration is an act of latria or religion?

Objection: 1. It would seem that adoration is not an act of latria or religion. The worship of religion is due to God alone. But adoration is not due to God alone: since we read (Gn 18,2) that Abraham adored the angels; and (1R 1,23) that the prophet Nathan, when he was come in to king David, "worshiped him bowing down to the ground." Therefore adoration is not an act of religion.
2. Further, the worship of religion is due to God as the object of beatitude, according to Augustine (De Civ. Dei x, 3): whereas adoration is due to Him by reason of His majesty, since a gloss on Ps 28,2, "Adore ye the Lord in His holy court," says: "We pass from these courts into the court where we adore His majesty." Therefore adoration is not an act of latria.
3. Further, the worship of one same religion is due to the three Persons. But we do not adore the three Persons with one adoration, for we genuflect at each separate invocation of Them [*At the adoration of the Cross, on Good Friday]. Therefore adoration is nol an act of latria.

On the contrary are the words quoted Mt 4,10: "The Lord thy God shalt thou adore and Him only shalt thou serve."
I answer that Adoration is directed to the reverence of the person adored. Now it is evident from what we have said (Question [81], Articles [2],4) that it is proper to religion to show reverence to God. Hence the adoration whereby we adore God is an act of religion.

Reply to Objection: 1. Reverence is due to God on account of His excellence, which is communicated to certain creatures not in equal measure, but according to a measure of proportion; and so the reverence which we pay to God, and which belongs to latria, differs from the reverence which we pay to certain excellent creatures; this belongs to dulia, and we shall speak of it further on (Question [103]). And since external actions are signs of internal reverence, certain external tokens significative of reverence are offered to creatures of excellence, and among these tokens the chief is adoration: yet there is one thing which is offered to God alone, and that is sacrifice. Hence Augustine says (De Civ. Dei x, 4): "Many tokens of Divine worship are employed in doing honor to men, either through excessive humility, or through pernicious flattery; yet so that those to whom these honors are given are recognized as being men to whom we owe esteem and reverence and even adoration if they be far above us. But who ever thought it his duty to sacrifice to any other than one whom he either knew or deemed or pretended to be a God?" Accordingly it was with the reverence due to an excellent creature that Nathan adored David; while it was the reverence due to God with which Mardochai refused to adore Aman fearing "lest he should transfer the honor of his God to a man" (Esther 13:14).Again with the reverence due to an excellent creature Abraham adored the angels, as did also Josue (Jos 5,15): though we may understand them to have adored, with the adoration of latria, God Who appeared and spoke to them in the guise of an angel. It was with the reverence due to God that John was forbidden to adore the angel (Ap 22,9), both to indicate the dignity which he had acquired through Christ, whereby man is made equal to an angel: wherefore the same text goes on: "I am thy fellow-servant and of thy brethren"; as also to exclude any occasion of idolatry, wherefore the text continues: "Adore God."
2. Every Divine excellency is included in His majesty: to which it pertains that we should be made happy in Him as in the sovereign good.
3. Since there is one excellence of the three Divine Persons, one honor and reverence is due to them and consequently one adoration. It is to represent this that where it is related (Gn 18,2) that three men appeared to Abraham, we are told that he addressed one, saying: "Lord, if I have found favor in thy sight," etc. The triple genuflection represents the Trinity of Persons, not a difference of adoration.

Whether adoration denotes an action of the body?

Objection: 1. It would seem that adoration does not denote an act of the body. It is written (Jn 4,23): "The true adorers shall adore the Father in spirit and in truth." Now what is done in spirit has nothing to do with an act of the body. Therefore adoration does not denote an act of the body.
2. Further, the word adoration is taken from "oratio" [prayer]. But prayer consists chiefly in an interior act, according to 1Co 14,15, "I will pray with the spirit, I will pray also with the understanding." Therefore adoration denotes chiefly a spiritual act.
3. Further, acts of the body pertain to sensible knowledge: whereas we approach God not by bodily but by spiritual sense. Therefore adoration does not denote an act of the body.

On the contrary A gloss on Ex 20,5, "Thou shalt not adore them, nor serve them," says: "Thou shalt neither worship them in mind, nor adore them outwardly."
I answer that As Damascene says (De Fide Orth. iv, 12), since we are composed of a twofold nature, intellectual and sensible, we offer God a twofold adoration; namely, a spiritual adoration, consisting in the internal devotion of the mind; and a bodily adoration, which consists in an exterior humbling of the body. And since in all acts of latria that which is without is referred to that which is within as being of greater import, it follows that exterior adoration is offered on account of interior adoration, in other words we exhibit signs of humility in our bodies in order to incite our affections to submit to God, since it is connatural to us to proceed from the sensible to the intelligible.

Reply to Objection: 1. Even bodily adoration is done in spirit, in so far as it proceeds from and is directed to spiritual devotion.
2. Just as prayer is primarily in the mind, and secondarily expressed in words, as stated above (Question [83], Article [12]), so too adoration consists chiefly in an interior reverence of God, but secondarily in certain bodily signs of humility; thus when we genuflect we signify our weakness in comparison with God, and when we prostrate ourselves we profess that we are nothing of ourselves.
3. Though we cannot reach God with the senses, our mind is urged by sensible signs to approach God.

Summa Th. II-II EN Qu.83 a.12