On the Trinity

Book I.

In which the unity and equality of the supreme trinity is established from the sacred scriptures, and some texts alleged against the equality of the son are explained.

Chapter 1.-This Work is Written Against Those Who Sophistically Assail the Faith of the Trinity, Through Misuse of Reason. They Who Dispute Concerning God Err from a Threefold Cause. Holy Scripture, Removing What is False, Leads Us on by Degrees to Things Divine. What True Immortality is. We are Nourished by Faith, that We May Be Enabled to Apprehend Things Divine.

1. The following dissertation concerning the Trinity, as the reader ought to be informed, has been written in order to guard against the sophistries of those who disdain to begin with faith, and are deceived by a crude and perverse love of reason. Now one class of such men endeavor to transfer to things incorporeal and spiritual the ideas they have formed, whether through experience of the bodily senses, or by natural human wit and diligent quickness, or by the aid of art, from things corporeal; so as to seek to measure and conceive of the former by the latter. Others, again, frame whatever sentiments they may have concerning God according to the nature or affections of the human mind; and through this error they govern their discourse, in disputing concerning God, by distorted and fallacious rules. While yet a third class strive indeed to transcend the whole creation, which doubtless is changeable, in order to raise their thought to the unchangeable substance, which is God; but being weighed down by the burden of mortality, whilst they both would seem to know what they do not, and cannot know what they would, preclude themselves from entering the very path of understanding, by an over-bold affirmation of their own presumptuous judgments; choosing rather not to correct their own opinion when it is perverse, than to change that which they have once defended. And, indeed, this is the common disease of all the three classes which I have mentioned,-viz., both of those who frame their thoughts of God according to things corporeal, and of those who do so according to the spiritual creature, such as is the soul; and of those who neither regard the body nor the spiritual creature, and yet think falsely about God; and are indeed so much the further from the truth, that nothing can be found answering to their conceptions, either in the body, or in the made or created spirit, or in the Creator Himself. For he who thinks, for instance, that God is white or red, is in error; and yet these things are found in the body. Again, he who thinks of God as now forgetting and now remembering, or anything of the same kind, is none the less in error; and yet these things are found in the mind. But he who thinks that God is of such power as to have generated Himself, is so much the more in error, because not only does God not so exist, but neither does the spiritual nor the bodily creature; for there is nothing whatever that generates its own existence.(1)

2. In order, therefore, that the human mind might be purged from falsities of this kind, Holy Scripture, which suits itself to babes has not avoided words drawn from any class of things really existing, through which, as by nourishment, our understanding might rise gradually to things divine and transcendent. For, in speaking of God, it has both used words taken from things corporeal, as when it says, "Hide me under the shadow of Thy wings;"(2) and it has borrowed many things from the spiritual creature, whereby to signify that which indeed is not so, but must needs so be said: as, for instance, "I the Lord thy God am a jealous God;"(3) and, "It repenteth me that I have made man."(4) But it has drawn no words whatever, whereby to frame either figures of speech or enigmatic sayings, from things which do not exist at all. And hence it is that they who are shut out from the truth by that third kind of error are more mischievously and emptily vain than their fellows; in that they surmise respecting God, what can neither be found in Himself nora in ny creature. For divine Scripture is wont to frame, as it were, allurements for children from the things which are found in the creature; whereby, according to their measure, and as it were by steps, the affections of the weak may be moved to seek those things that are above, and to leave those things that are below. But the same Scripture rarely employs those things which are spoken properly of God, and are not found in any creature; as, for instance, that which was said to Moses, "I am that I am;" and, "I Am hath sent me to you."(5) For since both body and soul also are said in some sense to be, Holy Scripture certainly would not so express itself unless it meant to be understood in some special sense of the term. So, too, that which the Apostle says, "Who only hath immortality."(6) Since the soul also both is said to be, and is, in a certain manner immortal, Scripture would not say "only hath," unless because true immortality is unchangeableness; which no creature can possess, since it belongs to the creator alone.(7) So also James says, "Every good gift and every perfect gift is from above, and cometh down from the Father of Lights, with whom is no variableness, neither shadow of turning."(8) So also David, "Thou, shall change them, and they shall be changed; but Thou art the same."(9)

3. Further, it is difficult to contemplate and fully know the substance of God; who fashions things changeable, yet without any change in Himself, and creates things temporal, yet without any temporal movement in Himself. And it is necessary, therefore, to purge our minds, in order to be able to see ineffably that which is ineffable; whereto not having yet attained, we are to be nourished by faith, and led by such ways as are more suited to our capacity, that we may be rendered apt and able to comprehend it. And hence the Apostle says, that "in Christ indeed are hid all the treasures of wisdom and knowledge;"(10) and yet has commended Him to us, as to babes in Christ, who, although already born again by His grace, yet are still carnal and psychical, not by that divine virtue wherein He is equal to the Father, but by that human infirmity whereby He was crucified. For he says, "I determined not to know anything among you, save Jesus Christ and Him crucified;"(11) and then he continues, "And I was with you in weakness, and in fear, and in much trembling." And a little after he says to them, "And I, brethren, could not speak unto you as unto spiritual, but as unto carnal,(12) even as unto babes in Christ. I have fed you with milk, and not with meat: for hitherto ye were not able to bear it, neither yet now are ye able."(13) There are some who are angry at language of this kind, and think it is used in slight to themselves, and for the most part prefer rather to believe that they who so speak to them have nothing to say, than that they themselves cannot understand what they have said. And sometimes, indeed, we do allege to them, not certainly that account of the case which they seek in their inquiries about God,-because neither can they themselves receive it, nor can we perhaps either apprehend or express it,-but such an account of it as to demonstrate to them how incapable and utterly unfit they are to understand that which they require of us. But they, on their parts, because they do not hear what they desire, think that we are either playing them false in order to conceal our own ignorance, or speaking in malice because we grudge them knowledge; and so go away indignant and perturbed.

Chapter 2.-In What Manner This Work Proposes to Discourse Concerning the Trinity.

4. Wherefore, our Lord God helping, we will undertake to render, as far as we are able, that very account which they so importunately demand: viz., that the Trinity is the one and only and true God, and also how the Father, the Son, and the Holy Spirit are rightly said, believed, understood, to be of one and the same substance or essence; in such wise that they may not fancy themselves mocked by excuses on our part, but may find by actual trial, both that the highest good is that which is discerned by the most purified minds, and that for this reason it cannot be discerned or understood by themselves, because the eye of the human mind, being weak, is dazzled in that so transcendent light, unless it be invigorated by the nourishment of the righteousness of faith. First, however, we must demonstrate, according to the authority of the Holy Scriptures, whether the faith be so. Then, if God be willing and aid us, we may perhaps at least so far serve these talkative arguers-more puffed up than capable, and therefore laboring under the more dangerous disease-as to enable them to find something which they are not able to doubt, that so, in that case where they cannot find the like, they may be led to lay the fault to their own minds, rather than to the truth itself or to our reasonings; and thus, if there be anything in them of either love or fear towards God, they may return and begin from faith in due order: perceiving at length how healthful a medicine has been provided for the faithful in the holy Church, whereby a heedful piety, healing the feebleness of the mind, may render it able to perceive the unchangeable truth, and hinder it from falling headlong, through disorderly rashness, into pestilent and false opinion. Neither will I myself shrink from inquiry, if I am anywhere in doubt; nor be ashamed to learn, if I am anywhere in error.

Chapter 3.-What Augustin Requests from His Readers. The Errors of Readers Dull of Comprehension Not to Be Ascribed to the Author.

5. Further let me ask of my reader, wherever, alike with myself, he is certain, there to go on with me; wherever, alike with myself, he hesitates, there to join with me in inquiring; wherever he recognizes himself to be in error, there to return to me; wherever he recognizes me to be so, there to call me back: so that we may enter together upon the path of charity, and advance towards Him of whom it is said, "Seek His face evermore."(14) And I would make this pious and safe agreement, in the presence of our Lord God, with all who read my writings, as well in all other cases as, above all, in the case of those which inquire into the unity of the Trinity, of the Father and the Son and the Holy Spirit; because in no other subject is error more dangerous, or inquiry more laborious, or the discovery of truth more profitable. If, then, any reader shall say, This is not well said, because I do not understand it; such an one finds fault with my language, not with my faith: and it might perhaps in very truth have been put more clearly; yet no man ever so spoke as to be understood in all things by all men. Let him, therefore, who finds this fault with my discourse, see whether he can understand other men who have handled similar subjects and questions, when he does not understand me: and if he can, let him put down my book, or even, if he pleases, throw it away; and let him spend labor and time rather on those whom he understands.(15) Yet let him not think on that account that I ought to have been silent, because I have not been able to express myself so smoothly and clearly to him as those do whom he understands. For neither do all things, which all men have written, come into the hands of all. And possibly some, who are capable of understanding even these our writings, may not find those more lucid works, and may meet with ours only. And therefore it is useful that many persons should write many books, differing in style but not in faith, concerning even the same questions, that the matter itself may reach the greatest number-some in one way, some in another. But if he who complains that he has not understood these things has never been able to comprehend any careful and exact reasonings at all upon such subjects, let him in that case deal with himself by resolution and study, that he may know better; not with me by quarrellings and wranglings, that I may hold my peace. Let him, again, who says, when he reads my book, Certainly I understand what is said, but it is not true, assert, if he pleases, his own opinion, and refute mine if he is able. And if he do this with charity and truth, and take the pains to make it known to me (if I am still alive), I shall then receive the most abundant fruit of this my labor. And if he cannot inform myself, most willing and glad should I be that he should inform those whom he can. Yet, for my part, "I meditate in the law of the Lord,"(16) if not "day and night," at least such short times as I can; and I commit my meditations to writing, lest they should escape me through forgetfulness; hoping by the mercy of God that He will make me hold steadfastly all truths of which I feel certain; "but if in anything I be otherwise minded, that He will himself reveal even this to me,"(17) whether through secret inspiration and admonition, or through His own plain utterances, or through the reasonings of my brethren. This I pray for, and this my trust and desire I commit to Him, who is sufficiently able to keep those things which He has given me, and to render those which He has promised.

6. I expect, indeed, that some, who are more dull of understanding, will imagine that in some parts of my books I have held sentiments which I have not held, or have not held those which I have. But their error, as none can be ignorant, ought not to be attributed to me, if they have deviated into false doctrine through following my steps without apprehending me, whilst I am compelled to pick my way through a hard and obscure subject: seeing that neither can any one, in any way, rightly ascribe the numerous and various errors of heretics to the holy testimonies themselves of the divine books; although all of them endeavor to defend out of those same Scriptures their own false and erroneous opinions. The law of Christ, that is, charity, admonishes me clearly, and commands me with a sweet constraint, that when men think that I have held in my books something false which I have not held, and that same falsehood displeases one and pleases another, I should prefer to be blamed by him who reprehends the falsehood, rather than praised by him who praises it. For although I, who never held the error, am not rightly blamed by the former, yet the error itself is rightly censured; whilst by the latter neither am I rightly praised, who am thought to have held that which the truth censures, nor the sentiment itself, which the truth also censures. Let us therefore essay the work which we have undertaken in the name of the Lord.

Chapter 4.-What the Doctrine of the Catholic Faith is Concerning the Trinity.

7. All those Catholic expounders of the divine Scriptures, both Old and New, whom I have been able to read, who have written before me concerning the Trinity, Who is God, have purposed to teach, according to the Scriptures, this doctrine, that the Father, and the Son, and the Holy Spirit intimate a divine unity of one and the same substance in an indivisible equality;(18) and therefore that they are not three Gods, but one God: although the Father hath begotten the Son, and so He who is the Father is not the Son; and the Son is begotten by the Father, and so He who is the Son is not the Father; and the Holy Spirit is neither the Father nor the Son, but only the Spirit of the Father and of the Son, Himself also co-equal with the Father and the Son, and pertaining to the unity of the Trinity. Yet not that this Trinity was born of the Virgin Mary, and crucified under Pontius Pilate, andand roseburied,, again the third day, and ascended into heaven, but only the Son. Nor, again, that this Trinity descended in the form of a dove upon Jesus when He was baptized;(19) nor that, on the day of Pentecost, after the ascension of the Lord, when "there came a sound from heaven, as of a rushing mighty wind,"(20) the same Trinity "sat upon each of them with cloven tongues like as of fire," but only the Holy Spirit. Nor yet that this Trinity said from heaven, "Thou art my Son,"(21) whether when He was baptized by John, or when the three disciples were with Him in the mount,(22) or when the voice sounded, saying, "I have both glorified it,and will glorify it again;"(23) but that it was a word of the Father only, spoken to the Son; although the Father, and the Son, and the Holy Spirit, as they are indivisible, so work indivisibly.(24) This is also my faith, since it is the Catholic faith.

Chapter 5.-Of Difficulties Concerning the Trinity: in What Manner Three are One God, and How, Working Indivisibly, They Yet Perform Some Things Severally.

8. Some persons, however, find a difficulty in this faith; when they hear that the Father is God, and the Son God, and the Holy Spirit God, and yet that this Trinity is not three Gods, but one God; and they ask how they are to understand this: especially when it is said that the Trinity works indivisibly in everything that God works, and yet that a certain voice of the Father spoke, which is not the voice of the Son; and that none except the Son was born in the flesh, and suffered, and rose again, and ascended into heaven; and that none except the Holy Spirit came in the form of a dove. They wish to understand how the Trinity uttered that voice which was only of the Father; and how the same Trinity created that flesh in which the Son only was born of the Virgin; and how the very same Trinity itself wrought that form of a dove, in which the Holy Spirit only appeared. Yet, otherwise, the Trinity does not work indivisibly, but the Father does some things, the Son other things, and the Holy Spirit yet others: or else, if they do some things together, some severally, then the Trinity is not indivisible. It is a difficulty, too, to them, in what manner the Holy Spirit is in the Trinity, whom neither the Father nor the Son, nor both, have begotten, although He is the Spirit both of the Father and of the Son. Since, then, men weary us with asking such questions, let us unfold to them, as we are able, whatever wisdom God's gift has bestowed upon our weakness on this subject; neither "let us go on our way with consuming envy."(25) Should we say that we are not accustomed to think about such things, it would not be true; yet if we acknowledge that such subjects commonly dwell in our thoughts, carried away as we are by the love of investigating the truth, then they require of us, by the law of charity, to make known to them what we have herein been able to find out. "Not as though I had already attained, either were already perfect" (for, if the Apostle Paul, how much more must I, who lie far beneath his feet, count myself not to have apprehended!); but, according to my measure, "if I forget those things that are behind, and reach forth unto those things which are before, and press towards the mark for the prize of the high calling,"(26) I am requested to disclose so much of the road as I have already passed, and the point to which I have reached, whence the course yet remains to bring me to the end. And those make the request, whom a generous charity compels me to serve. Needs must too, and God will grant that, in supplying them with matter to read, I shall profit myself also; and that, in seeking to reply to their inquiries, I shall myself likewise find that for which I was inquiring. Accordingly I have undertaken the task, by the bidding and help of the Lord my God, not so much of discoursing with authority respecting things I know already, as of learning those things by piously discoursing of them.

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  1. [Augustin here puts generare for creare-which is rarely the case with him, since the distinction between generation and creation is of the highest importance in discussing the doctrine of the Trinity. His thought here is, that God does not bring himself into being, because he always is. Some have defined God as the Self-caused: causa sut. But the category of cause and effect is inapplicable to the Infinite Being.-W. G. T. S.]
  2. Ps. xvii. 8.
  3. Ex. xx. 5.
  4. Gen. vi. 7.
  5. Ex. iii. 14.
  6. 1 Tim. vi. 16.
  7. [God's being is necessary; that of the creature is contingent. Hence the name I Am, or Jehovah,-which denotes this difference. God alone has immortality a parte ante, as well as a parte post.-W. G. T. S.].
  8. Jas. i. 17.
  9. Ps. cii. 26, 27.
  10. Col. ii. 3.
  11. 1 Cor. ii. 2, 3.
  12. [St.Paul,, in this place, denominates imperfect but true believers "carnal," in a relative sense, only. They are comparatively carnal, when contrasted with the law of God, which is absolutely and perfectly spiritual. (Rom. vii. 14.) They do not, however, belong to the class of carnal or natural men, in distinction from spiritual. The persons whom the Apostle here denominates "carnal," are "babes in Christ."-W. G. T. S.]
  13. 1 Cor. iii. 1, 2.
  14. Ps. cv. 4.
  15. [This request of Augustin to his reader, involves an admirable rule for authorship generally-the desire, namely, that truth be attained, be it through himself or through others. MiIton teaches the same, when he says that the author must "study and love learning for itself, not for lucre, or any other end, but the service of God and of truth, and perhaps that lasting fame and perpetuity of praise, which God and good men have consented shall be the reward of those whose published labors advance the good of mankind."-W. G. T. S.].
  16. Ps. i. 2.
  17. Phil. iii. 15.
  18. [Augustin teaches the Nicene doctrine of a numerical unity of essence in distinction from a specific unity. The latter is that of mankind. In this case there is division of substance-part after part of the specific nature being separated and formed, by propagation, into individuals. No human individual contains the whole specific nature. But in the case of the numerical unity of the Trinity, there is no division of essence. The whole divine nature is in each divine person. The three divine persons do not constitute a species-that is, three divine individuals made by the division and distribution of one common divine nature-but are three modes or "forms" (Phil. ii. 6) of one undivided substance, numerically and identically the same in each.-W. G. T. S.].
  19. Matt. iii. 16.
  20. Acts. ii. 2,Acts ii. 4.
  21. Mark i. 11.
  22. Matt. xvii. 5.
  23. John xii. 28.
  24. [The term Trinity denotes the Divine essence in all three modes. The term Father (or Son, or Spirit) denotes the essence in only one mode. Consequently, there is something in the Trinity that cannot be attributed to any one of the Persons, as such; and something in a Person that cannot be attributed to the Trinity, as such. Trinality cannot be ascribed to the first Person; paternity cannot be ascribed to the Trinity.-W. G. T. S.]
  25. Wisd. vi. 23.
  26. Phil. iii. 12-14.