The Catechism of Trent

In Dominico Agro

Encyclical of Pope Clement XIII promulgated on June 14, 1761.

To the Venerable Brothers, the Patriarchs, Primates, Archbishops and Bishops. Venerable Brothers, Greetings and Apostolic Benediction.

In the Lord's field, for the tending of which Divine Providence placed Us as overseer, there is nothing which demands as much vigilant care and unremitting labor in its cultivation than guarding the good seed of Catholic teaching which the Apostles received from Jesus Christ and handed on to Us. If in laziness this is neglected, the enemy of the human race will sow weeds while the workers sleep. Then weeds will be found which should be committed to the flames rather than good grain to store in the barns. However, St. Paul strongly encourages Us to protect the faith that the saints handed on to Us.(
Jud 1,3) He told Timothy to preserve the sacred trust (2Tm 1,14) because dangerous times were coming (cf 2Tm 3,1) when evil and deceitful men would exist in the Church of God.( cf 2Tm 3,13)

The insidious tempters would use their work to try to infect unwary minds with errors which are hostile to evangelical truth. It often happens that certain unworthy ideas come forth in the Church of God which, although they directly contradict each other, plot together to undermine the purity of the Catholic faith in some way. It is very difficult to cautiously balance our speech between both enemies in such a way that We seem to turn Our backs on none of them, but to shun and condemn both enemies of Christ equally. Meanwhile the matter is such that diabolical error, when it has artfully colored its lies, easily clothes itself in the likeness of truth while very brief additions or changes corrupt the meaning of expressions; and confession, which usually works salvation, sometimes, with a slight change, inches toward death.

The faithful -- especially those who are simple or uncultivated -- should be kept away from dangerous and narrow paths upon which they can hardly set foot without faltering. The sheep should not be led to pasture through trackless places. Nor should peculiar ideas -- even those of Catholic scholars -- be proposed to them. Rather, only those ideas should be communicated which are definitely marked as Catholic truth by their universality, ambiguity, and harmony. Besides, since the crowd cannot go up to the mountain(cf
Ex 19,12) upon which the glory of the Lord came down, and if whoever crosses the boundaries to see will die, the teachers of the people should establish boundaries around them so that no word strays beyond that which is necessary or useful for salvation. The faithful should obey the apostolic advice not to know more than is necessary, but to know in moderation.(Rm 12,3)

4 The popes clearly understood this. They devoted all their efforts not only to cut short with the sword of anathema the poisonous buds of growing error, but also to cut away certain developing ideas which either could prevent the Christian people unnecessarily from bearing a greater fruit of faith or could harm the minds of the faithful by their proximity to error. So the Council of Trent condemned those heresies which tried at that time to dim the light of the Church and which led Catholic truth into a clearer light as if the cloud of errors had been dispersed. As our predecessors understood that that holy meeting of the universal Church was so prudent in judgment and so moderate that it abstained from condemning ideas which authorities among Church scholars supported, they wanted another work prepared with the agreement of that holy council which would cover the entire teaching which the faithful should know and which would be far removed from any error. They printed and distributed this book under the title of The Roman Catechism. There are aspects of their action worthy of special praise. In it they compiled the teaching which is common to the whole Church and which is far removed from every danger of error, and they proposed to transmit it openly to the faithful in very eloquent words according to the precept of Christ the Lord who told the apostles to proclaim in the light what He had said in the dark and to proclaim from the rooftops what they heard in secret.(cf Mt 10,27) They have obeyed His bride, the Church, whose words are, "Show me where you recline at midday."(Ct 1,6) For where it is not midday and the light is not so bright that truth can be clearly known, error can easily be mistaken for truth because of its appearance of truth and can be distinguished from truth only with difficulty in the darkness. They knew that there were before and would again be people who attract those who seek food by the promise of more abundant pastures of wisdom and knowledge and that many people would come to those pastures because stolen waters are sweeter and hidden bread more delightful.(Pr 9,17) Therefore, in case the Church should be deceived and wander after the flocks of the companions who are themselves wanderers and unsettled with no certainty of truth, who are always learning(2Tm 3,7) but never arriving at the knowledge of truth, they proposed that only what is necessary and very useful for salvation be clearly and plainly explained in the Roman Catechism and communicated to the faithful.

But even though this book, composed with remarkable work and effort, was universally approved and welcomed with the highest praises, at that time, the love of novelty almost wrested it from the priests' hands by inspiring the production of more and more catechisms which could compare in no way with the Roman Catechism. Thus two evils arose. Agreement on a method of teaching was almost destroyed, and the weak members of the faithful were scandalized at finding that they were no longer united by the same language and topics (
Gn 11,1). On the other hand, contentions arose from different ways of transmitting Catholic truth and disunity of spirit and great disagreements from rivalry while one declared he was a follower of Apollo, another of Cephas, and another of Paul. We think that nothing can be more fatal to God's greater glory than the bitterness of those disagreements. Nothing can eliminate more disastrously the fruits which the faithful should gain from Christian discipline. Thus, in order to remove the double evil from the Church, We must return to that method from which some, setting themselves up in the Church as wiser, have insolently and imprudently led the faithful away for some time. We think that the Roman Catechism should be offered to the priests again so that just as it once strengthened the Catholic faith and strengthened the minds of the faithful in the Church's teaching which is the pillar of truth,(1Tm 3,15) it may now turn them away from new ideas which neither antiquity nor unanimity recommend. To make the book more easily accessible and to correct the errors which have occurred in course of production, We have ensured that the copy published by Our predecessor St. Pius V in accordance with the decree of the Council of Trent is reprinted in Rome with all care. The vernacular translation of it which was made and published by order of the same St. Pius will be reprinted very soon by Our order and will finally be published.

6 So since Our care and diligence are providing a very suitable aid to remove the deceptions of wicked ideas at this very difficult time for the Church and to spread and establish true and sound teaching, it is your duty to see to it that the faithful accept it. Because the popes wanted this book set before pastors almost as the norm of Catholic faith and Christian discipline in order that unanimity might exist also in the method of transmitting doctrine, We now strongly recommend it to you, venerable brothers. We strongly encourage you to order that everybody who has the care of souls should use it in instructing the faithful in the Catholic truth in order to preserve unity of learning, charity, and harmony of spirits. For it is your duty to be attentive to everybody's serenity. Finally, it is the bishop's duty to watch carefully that nobody breaks the bond of unity and creates schisms by proudly acting in his own interests.

7 If those who ought to present and explain these books to the faithful are unsuitable teachers, they will prove useless or almost useless. Therefore, it is of the utmost importance that you choose for the office of communicating Christian teaching to the faithful not only men endowed with theological knowledge, but more importantly, men who manifest humility, enthusiasm for sanctifying souls, and charity. The totality of Christian practice does not consist in abundance of words nor in skill of debating nor in the search from praise and glory but in true and voluntary humility. There are those whom a greater wisdom raises up but also separates from the society of other people. The more they know, the more they dislike the virtue of harmony. Wisdom itself warns them with the word of God: "Have salt in yourselves and be at peace among us."(Mc 9,49) Thus it is necessary to have the salt of wisdom to preserve the love of neighbor and to offset weaknesses. If they turn from zeal for wisdom and from concern for their neighbor to disagreement, they have salt without peace-not a gift of virtue but a cause for condemnation. The more they know, the worse they fail. The Apostle James condemns them with these words: "If you are jealous and have contentions in your hearts, do not boast and be liars against the truth. This wisdom did not come down from on high. Rather, it is earthly, animal, diabolical. Inconstancy and every wicked deed accompany jealousy and contention. The wisdom which comes from on high is first of all pure. Then it is peaceful, modest, persuasive, agreeable to good things, full of mercy and good fruits. It does not judge and is without rivalry."(Jc 3,14)

8 Therefore, while We pray to God in affliction of spirit and in humility of heart to bestow his indulgence and mercy on our efforts to prevent disagreement disturbing the faithful, and to ensure that in the bond of peace and in charity of spirit, we all know, praise, and glorify the one God and our Lord Jesus Christ, We greet you with a holy kiss and We lovingly impart Our apostolic blessing to all of you and to all the faithful of your churches.

Given at Castel Gandolfo on the 14th day of June, 1761, the third year of Our Pontificate.

Pope Clement XIII

The Catechism of Trent


Issued by order of Pope Pius V



The Necessity Of Religious Instruction

Such is the nature of the human mind and intellect that, although by means of diligent and laborious inquiry it has of itself investigated and discovered many other things pertaining to a knowledge of divine truths; yet guided by its natural lights it never could have known or perceived most of those things by which is attained eternal salvation, the principal end of man's creation and formation to the image and likeness of God.

It is true that the invisible things of God from the creation of the world are, as the Apostle teaches, clearly seen, being understood by the things that are made: his eternal power also, and divinity. But the mystery which hath been hidden from ages and generations so far transcends the reach of man's understanding, that were it not made manifest by God to His Saints, to whom He willed to make known by the gift of faith, the riches of the glory of this mystery among the Gentiles, which is Christ, man could by no effort attain to such wisdom.

But, as faith comes by hearing, it is clear how necessary at all times for the attainment of eternal salvation has been the labour and faithful ministry of an authorised teacher; for it is written, how shall they hear, without a preacher? And how shall they preach unless they be sent?

And, indeed, never, from the very creation of the world, has God, most merciful and benignant, been wanting to His own; but at sundry times and in divers manners spoke to the fathers by the prophets, and pointed out to them in a manner suited to the times and circumstances, a sure and direct path to the happiness of heaven. But, as He had foretold that He would give a teacher of justice to be the light of the Gentiles, that His salvation might reach even to the ends of the earth, in these last days he hath spoken to us by his Son, whom also by a voice from heaven, from the excellent glory, He has commanded all to hear and to obey. Furthermore, the Son gave some to be apostles, and some prophets, and others pastors and teachers, to announce the word of life; that we might not be carried about like children tossed to and fro with every wind of doctrine, but holding fast to the firm foundation of the faith, we might be built together into an habitation of God in the Spirit.

Lest any should receive the Word of God from the ministers of the Church, not as the word of Christ, which it really is, but as the word of man, the same Saviour has ordained that their ministry should be invested with so great authority that He says to them: He that hears you, hears me; and he that despises you despises me. These words He spoke not only of those to whom His words were addressed, but likewise of all who, by legitimate succession, should discharge the ministry of the word, promising to be with them all days even to the consummation of the world.

Need of an Authoritative Catholic Catechism

But while the preaching of the divine Word should never be interrupted in the Church, surely in these, our days, it becomes necessary to labour with more than ordinary zeal and piety to nourish and strengthen the faithful with sound and wholesome doctrine, as with the food of life. For false prophets have gone forth into the world, to corrupt the minds of the faithful with various and strange doctrines, of whom the Lord has said: I did not send prophets, yet they ran; I spoke not to them, yet they prophesied.

In this work, to such extremes has their impiety, practiced in all the arts of Satan, been carried, that it would seem almost impossible to confine it within any bounds; and did we not rely on the splendid promises of the Saviour, who declared that He had built His Church on so solid a foundation that the gates of hell shall not prevail against it, we should have good reason to fear lest, beset on every side by such a host of enemies and assailed and attacked by so many machinations, it would, in these days, fall to the ground.

For ­ to say nothing of those illustrious States which heretofore professed, in piety and holiness, the true Catholic faith transmitted to them by their ancestors, but are now gone astray wandering from the paths of truth and openly declaring that their best claims to piety are founded on a total abandonment of the faith of their fathers ­ there is no region, however remote, no place, however securely guarded, no corner of Christendom, into which this pestilence has not sought secretly to insinuate itself.

For those who intended to corrupt the minds of the faithful, knowing that they could not hold immediate personal intercourse with all, and thus pour into their ears their poisoned doctrines, adopted another plan which enabled them to disseminate error and impiety more easily and extensively. Besides those voluminous works by which they sought the subversion of the Catholic faith ­ to guard against which (volumes) required perhaps little labour or circumspection, since their contents were clearly heretical ­ they also composed innumerable smaller books, which, veiling their errors under the semblance of piety, deceived with incredible facility the unsuspecting minds of simple folk.

The Nature of this Work

The Fathers, therefore, of the General Council of Trent, anxious to apply some healing remedy to so great and pernicious an evil, were not satisfied with having decided the more important points of Catholic doctrine against the heresies of our times, but deemed it further necessary to issue, for the instruction of the faithful in the very rudiments of faith, a form and method to be followed in all churches by those to whom are lawfully entrusted the duties of pastor and teacher.

To works of this kind many, it is true, had already given their attention, and earned the reputation of great piety and learning. But the Fathers deemed it of the first importance that a work should appear, sanctioned by the authority of the Council, from which pastors and all others on whom the duty of imparting instruction devolves, may be able to seek and find reliable matter for the edification of the faithful; that, as there is one Lord, one faith, there may also be one standard and prescribed form of propounding the dogmas of faith, and instructing Christians in all the duties of piety.

As, therefore, the design of the work embraces a variety of matters, it cannot be supposed that the Council intended that in one volume all the dogmas of Christianity should be explained with that minuteness of detail to be found in the works of those who profess to treat the teaching and doctrines of religion in their entirety. Such a task would be one of almost endless labour, and manifestly ill suited to attain the proposed end. But, having undertaken to instruct pastors and such as have care of souls in those things that belong peculiarly to the pastoral office and are accommodated to the capacity of the faithful, the Council intended that such things only should be treated of as might assist the pious zeal of pastors in discharging the duty of instruction, should they not be very familiar with the more abstruse questions of theology.

The Ends of Religious Instruction

Hence, before we proceed to develop in detail the various parts of this summary of doctrine, our purpose requires that we premise a few observations which the pastor should consider and bear in mind in order to know to what end, as it were, all his plans and labours and efforts are to be directed, and how this desired end may be more easily attained.

Knowledge Of Christ

The first thing is ever to recollect that all Christian knowledge is reduced to one single head, or rather, to use the words of the Apostle, this is eternal life: That they may know thee, the only true God, and Jesus Christ, whom thou hast sent. A teacher in the Church should, therefore, use his best endeavours that the faithful earnestly desire to know Jesus Christ, and him crucified, that they be firmly convinced, and with the most heartfelt piety and devotion believe, that there is no other name under heaven given to men, whereby we must be saved, for he is the propitiation for our sins.

Observance Of The Commandments

But since by this we know that we have known him, if we keep his commandments, the next consideration, and one intimately connected with the preceding, is to press also upon the attention of the faithful that their lives are not to be wasted in ease and indolence, but that we are to walk even as he walked, and pursue with all earnestness, justice, godliness, faith, charity, patience, mildness; for He gave himself for us, that he might redeem us from all iniquity, and might cleanse to himself a people acceptable, a pursuer of good works. These things the Apostle commands pastors to speak and exhort.

Love Of God

But as our Lord and Saviour has not only declared, but has also proved by His own example, that the Law and the Prophets depend on love, and as, according to the Apostle, charity is the end of the commandment, and the fulfilment of the law, it is unquestionably a chief duty of the pastor to use the utmost diligence to excite the faithful to a love of the infinite goodness of God towards us, that, burning with a sort of divine ardour, they may be powerfully attracted to the supreme and all­perfect good, to adhere to which is true and solid happiness, as is fully experienced by him who can say with the Prophet: What have I in heaven? and besides thee what do I desire upon earth?

This, assuredly, is that more excellent way pointed out by the Apostle when he sums up all his doctrines and instructions in charity, which never falleth away. For whatever is proposed by the pastor, whether it be the exercise of faith, of hope, or of some moral virtue, the love of our Lord should at the same time be so strongly insisted upon as to show clearly that all the works of perfect Christian virtue can have no other origin, no other end than divine love.

The Means Required for Religious Instruction

But as in imparting instruction of any sort the manner of communicating it is of highest importance, so in conveying religious instruction to the people, the method should be deemed of the greatest moment.

Instruction Should Be Accommodated To The Capacity Of The Hearer

Age, capacity, manners and condition must be borne in mind, so that he who instructs may become all things to all men, in order that he may be able to gain all to Christ, prove himself a dutiful minister and steward, and, like a good and faithful servant, be found worthy to be placed by his Lord over many things The priest must not imagine that those committed to his care are all on the same level, so that he can follow one fixed and unvarying method of instruction to lead all in the same way to knowledge and true piety; for some are as new­born infants, others are growing up in Christ, while a few are, so to say, of full maturity. Hence the necessity of considering who they are that have occasion for milk, who for more solid food, and of affording to each such nourishment of doctrine as may give spiritual increase, until we all meet in the unity of faith, and of the knowledge of the Son of God, unto a perfect man, unto the measure of the age of the fullness of Christ. This the Apostle inculcates for all by his own example when he says that he is a debtor to the Greeks and to the Barbarians, to the wise and to the unwise, thus giving all who are called to this ministry to understand that in announcing the mysteries of faith and the precepts of life, the instruction is to be so accommodated to the capacity and intelligence of the hearers, that, while the minds of the strong are filled with spiritual food, the little ones be not suffered to perish with hunger, asking for bread, while there is none to break it unto them.


Nor should our zeal in communicating Christian knowledge be relaxed because it has sometimes to be exercised in expounding matters apparently humble and unimportant, and whose exposition is usually irksome, especially to minds accustomed to the contemplation of the more sublime truths of religion. If the Wisdom of the eternal Father descended upon the earth in the meanness of our flesh to teach us the maxims of a heavenly life, who is there whom the love of Christ does not constrain to become little in the midst of his brethren, and, as a nurse fostering her children, so anxiously to wish for the salvation of his neighbours as to be ready, as the Apostle says of himself, to give them not only the gospel of God, but even his own life.

Study Of The Word Of God

Now all the doctrines in which the faithful are to be instructed are contained in the Word of God, which is found in Scripture and tradition. To the study of these, therefore, the pastor should devote his days and his nights, keeping in mind the admonition of St. Paul to Timothy, which all who have the care of souls should consider as addressed to themselves: Attend to reading, to exhortation, and to doctrine, for all Scripture divinely inspired is profitable to teach, to reprove, to correct, to instruct injustice, that the man of God may be perfect, furnished to every good work.

Division of this Catechism

The truths revealed by Almighty God are so many and so various that it is no easy task to acquire a knowledge of them, or, having done so, to remember them so well as to be able to explain them with ease and readiness when occasion requires. Hence our predecessors in the faith have very wisely reduced all the doctrines of salvation to these four heads: The Apostles' Creed, the Sacraments, the Ten Commandments, and the Lord's Prayer.

The part on the Creed contains all that is to be held according to Christian faith, whether it regard the knowledge of God, the creation and government of the world, or the redemption of man, the rewards of the good and the punishments of the wicked. The part devoted to the Seven Sacraments teaches us what are the signs, and, as it were, the instruments of grace. In the part on the Decalogue is described whatever has reference to the law, whose end is charity. Finally, the Lord's Prayer contains whatever can be the object of the Christian's desires, or hopes, or prayers. The exposition, therefore, of these four parts, which are, as it were, the general heads of Sacred Scripture, includes almost everything that a Christian should learn.

How This Work Is To Be Used

We therefore deem it proper to inform pastors that, whenever they have occasion, in the ordinary discharge of their duty, to expound any passage of the Gospel or any other part of Holy Scripture. they will find its subject­matter treated under some one of the four heads already enumerated, to which they recur, as to the source from which their instruction is to be drawn.

Thus, if the Gospel of the first Sunday of Advent is to be explained, There shall be signs in the sun, and in the moon, etc., whatever regards its explanation is contained under the Article of the Creed, He shall come to judge the living and the dead; and by embodying the substance of that Article in his exposition, the pastor will at once instruct his people in the Creed and in the Gospel. Whenever, therefore, he has to communicate instruction and expound the Scriptures, he will observe the same rule of referring all to these four principal heads under which, as we observed, the whole teaching and doctrine of Holy Scripture is contained. As for order, however, he is free to follow that which he deems best suited to the circumstances of persons and time.




In preparing and instructing men in the teachings of Christ the Lord, the Fathers began by explaining the meaning of faith. Following their example, we have thought it well to treat first what pertains to that virtue.

Though the word faith has a variety of meanings in the Sacred Scriptures, we here speak only of that faith by which we yield our entire assent to whatever has been divinely revealed.

Necessity Of Faith

That faith thus understood is necessary to salvation no man can reasonably doubt, particularly since it is written: Without faith it is impossible to please God. For as the end proposed to man as his ultimate happiness is far above the reach of human understanding, it was therefore necessary that it should be made known to him by God. This knowledge, however, is nothing else than faith, by which we yield our unhesitating assent to whatever the authority of our Holy Mother the Church teaches us to have been revealed by God; for the faithful cannot doubt those things of which God, who is truth itself, is the author. Hence we see the great difference that exists between this faith which we give to God and that which we yield to the writers of human history.

Unity Of Faith

Faith differs in degree; for we read in Scripture these words: O thou of little faith, why didst thou doubt; and Great is thy faith; and Increase our faith. It also differs in dignity, for we read: Faith without works is dead; and, Faith that worketh by charity. But although faith is so comprehensive, it is yet the same in kind, and the full force of its definition applies equally to all its varieties. How fruitful it is and how great are the advantages we may derive from it we shall point out when explaining the Articles of the Creed.

The Creed

Now the chief truths which Christians ought to hold are those which the holy Apostles, the leaders and teachers of the faith, inspired by the Holy Ghost' have divided into the twelve Articles of the Creed. For having received a command from the Lord to go forth into the whole world, as His ambassadors, and preach the Gospel to every creature, they thought it advisable to draw up a formula of Christian faith, that all might think and speak the same thing, and that among those whom they should have called to the unity of the faith no schisms would exist, but that they should be perfect in the same mind, and in the same judgment.

This profession of Christian faith and hope, drawn up by themselves, the Apostles called a symbol; either because it was made up of various parts, each of which was contributed by an Apostle, or because by it, as by a common sign and watchword, they might easily distinguish deserters from the faith and false brethren unawares brought in, adulterating the word of God, from those who had truly bound themselves by oath to serve under the banner of Christ.

Division Of The Creed

Christianity proposes to the faithful many truths which, either separately or in general, must be held with an assured and firm faith. Among these what must first and necessarily be believed by all is that which God Himself has taught us as the foundation and summary of truth concerning the unity of the Divine Essence, the distinction of Three Persons, and the actions which are peculiarly attributed to each. The pastor should teach that the Apostles, Creed briefly comprehends the doctrine of this mystery.

For, as has been observed by our predecessors in the faith, who have treated this subject with great piety and accuracy, the Creed seems to be divided into three principal parts: one describing the First Person of the Divine Nature, and the stupendous work of the creation; another, the Second Person, and the mystery of man's redemption; a third, the Third Person, the head and source of our sanctification; the whole being expressed in various and most appropriate propositions. These propositions are called Articles, from a comparison frequently used by the Fathers; for as the members of the body are divided by joints (articuli), so in this profession of faith, whatever is to be believed distinctly and separately from anything else is rightly and suitably called an Article.



Meaning Of This Article

The meaning of the above words is this: I believe with certainty, and without a shadow of doubt profess my belief in God the Father, the First Person of the Trinity, who by His omnipotence created from nothing and preserves and governs the heavens and the earth and all things which they contain; and not only do I believe in Him from my heart and profess this belief with my lips, but with the greatest ardour and piety I tend towards Him, as the supreme and most perfect good.

Let this serve as a brief summary of this first Article. But since great mysteries lie concealed under almost every word, the pastor must now give them a more careful consideration, in order that, as far as God has permitted, the faithful may approach, with fear and trembling, to contemplate the glory of His majesty.

"I Believe"

1011 The word believe does not here mean to think, to suppose, lo be of opinion; but, as the Sacred Scriptures teach, it expresses the deepest conviction, by which the mind gives a firm and unhesitating assent to God revealing His mysterious truths. As far, therefore, as regards use of the word here, he who firmly and without hesitation is convinced of anything is said to believe.

Faith Excludes Doubt

The knowledge derived through faith must not be considered less certain because its objects are not seen; for the divine light by which we know them, although it does not render them evident, yet suffers us not to doubt them. For God, who commanded the light to shine out of darkness, hath himself shone in our hearts, that the gospel be not hidden to us, as to those that perish.

Faith Excludes Curiosity

From what has been said it follows that he who is gifted with this heavenly knowledge of faith is free from an inquisitive curiosity. For when God commands us to believe He does not propose to us to search into His divine judgments, or inquire into their reason and cause, but demands an unchangeable faith, by which the mind rests content in the knowledge of eternal truth. And indeed, since we have the testimony of the Apostle that God is true; and every man a liar, and since it would argue arrogance and presumption to disbelieve the word of a grave and sensible man affirming anything as true, and to demand that he prove his statements by arguments or witnesses, how rash and foolish are those, who, hearing the words of God Himself, demand reasons for His heavenly and saving doctrines? Faith, therefore, must exclude not only all doubt, but all desire for demonstration.

Faith Requires Open Profession

The pastor should also teach that he who says, I believe, besides declaring the inward assent of the mind, which is an internal act of faith, should also openly profess and with alacrity acknowledge and proclaim what he inwardly and in his heart believes. For the faithful should be animated by the same spirit that spoke by the lips of the Prophet when he said: I believe; and therefore did I speak, and should follow the example of the Apostles who replied to the princes of the people: We cannot but speak the things which we have seen and heard. They should be encouraged by these noble words of St. Paul: I am not ashamed of the gospel. For it is the power of God unto salvation to every one that believeth; and likewise by those other words; in which the truth of this doctrine is expressly confirmed: With the heart we believe unto justice; but with the mouth confession is made unto salvation.

The Catechism of Trent