Isaias 43:10

“You think that these words refer to the stranger and the proselytes, but in fact they refer to us who have been illumined by Jesus. For Christ would have borne witness even to them; but now you are become twofold more the children of hell, as He said Himself. Therefore what was written by the prophets was spoken not of those persons, but of us, concerning whom the Scripture speaks: ‘I will lead the blind by a way which they knew not; and they shall walk in paths which they have not known. And I am witness, saith the Lord God, and my servant whom I have chosen.’ To whom, then, does Christ bear witness? Manifestly to those who have believed. But the proselytes not only do not believe, but twofold more than yourselves blaspheme His name, and wish to torture and put to death us who believe in Him; for in all points they strive to be like you. …

2. Wherefore, as I have already stated, no other is named as God, or is called Lord, except Him who is God and Lord of all, who also said to Moses, “ I am that I am . And thus shalt thou say to the children of Israel: He who is, hath sent me unto you;” and His Son Jesus Christ our Lord, who makes those that believe in His name the sons of God. And again, when the Son speaks to Moses, He says, “I am come down to deliver this people.” For it is He who descended and ascended for the salvation of men. Therefore God has been declared through the Son, who is in the Father, and has the Father in Himself, He who is, the Father bearing witness to the Son, and the Son announcing the Father. As also Esaias says, “I too am witness,” he declares, “saith the Lord God, and the Son whom I have chosen, that ye may know, and believe, and understand that I am.”

If we satisfied ourselves with advancing such considerations as these, our doctrines might by some be looked upon as human. But, since the voices of the prophets confirm our arguments, for I think that you also, with your great zeal for knowledge, and your great attainments in learning, cannot be ignorant of the writings either of Moses or of Isaiah and Jeremiah, and the other prophets, who, lifted in ecstasy above the natural operations of their minds by the impulses of the Divine Spirit, uttered the things with which they were inspired, the Spirit making use of them as a flute-player breathes into a flute; what, then, do these men say? “The Lord is our God; no other can be compared with Him.” And again: “I am God, the first and the last, and besides Me there is no God.” In like manner: “Before Me there was no other God, and after Me there shall be none; I am God, and there is none besi …

VI. Hence the aged Simeon, putting off the weakness of the flesh, and putting on the strength of hope, in the face of the law hastened to receive the Minister of the law, the Teacher with authority, the God of Abraham, the Protector of Isaac, the Holy One of Israel, the Instructor of Moses; Him, I say, who promised to show him His divine incarnation, as it were His hinder parts; Him who, in the midst of poverty, was rich; Him who in infancy was before the ages; Him who, though seen, was invisible; Him who in comprehension was incomprehensible; Him who, though in littleness, yet surpassed all magnitude, at one and the same time in the temple and in the highest heavens, on a royal throne, and on the chariot of the cherubim Him who is both above and below continuously; Him who is in the form of a servant, and in the form of God the Father; a subject, and yet King of all. …

“He came for a witness that He might bear witness of the light, that all through Him might believe.” Some of the dissenters from the Church’s doctrine, men who profess to believe in Christ, have desired another being, as indeed their system requires, besides the Creator, and hence cannot allow His coming to the world to have been foretold by the prophets. They therefore endeavour to get rid of the testimonies of the prophets about Christ, and say that the Son of God has no need of witnesses, but that He brings with Him His own evidence, partly in the sound words full of power which He proclaimed and partly in the wonderful works He did, which were sufficient at once to convince any one whatever. …

And I know indeed that what now has been said cannot by many be comprehended, and therefore it is that in many places we avoid agitating questions of human reasonings, because the rest of the people cannot follow such arguments, and if they could, still they have nothing firm or sure in them. “For the thoughts of mortal men are miserable, and our devices are but uncertain.” ( Wisd. ix. 14 .) Still I should like to ask our objectors, what means that which is said by the Prophet, “Before Me there was no God formed, nor is there any after Me”? ( Is. xliii. 10 .) For if the Son is younger than the Father, how, says He, “Nor is there any after me”? Will you take away the being of the Only-Begotten Himself? You either must dare this, or admit one Godhead with distinct Persons of the Father and Son.

Finally, how could the expression, “All things were made by Him,” be true? For if there is an age older than He, how can that which was before Him have been made by Him? See ye to what daring the argument has carried them, when once the truth has been unsettled? Why did not the Evangelist say, that He was made from things that were not, as Paul declares of all things, when he says, “Who calleth those things which be not as though they were”; but says, “Was in the beginning”? ( Rom. iv. 17 .) This is contrary to that; and with good reason. For God neither is made, nor has anything older; these are words of the Greeks. …

[3.] “He hath declared Him,” saith John. What hath he declared? That “no man hath seen God at any time”? That “God is one”? But this all the other prophets testify, and Moses continually exclaims, “The Lord thy God is one Lord” ( Deut. vi. 4 ); and Esaias, “Before Me there was no God formed, neither shall there be after me.” ( Isa. xliii. 10 .) What more then have we learned from “the Son which is in the bosom of the Father”? What from “the Only-Begotten”? In the first place, these very words were uttered by His working; in the next place, we have received a teaching that is far clearer, and learned that “God is a spirit, and they that worship Him must worship Him in spirit and in truth” ( c. iv. 24 ); and again, that it is impossible to see God; “that no man knoweth” Him, “save the Son” ( Matt. xi. …

XXIII. Again, where do you get your Unbegotten and Unoriginate, those two citadels of your position, or we our Immortal? Show me these in so many words, or we shall either set them aside, or erase them as not contained in Scripture; and you are slain by your own principle, the names you rely on being overthrown, and therewith the wall of refuge in which you trusted. Is it not evident that they are due to passages which imply them, though the words do not actually occur? What are these passages? I am the first, and I am the last, and before Me there was no God, neither shall there be after Me. For all that depends on that Am makes for my side, for it has neither beginning nor ending. When you accept this, that nothing is before Him, and that He has not an older Cause, you have implicitly given Him the titles Unbegotten and Unoriginate. …

35. You know the words, Hear, O Israel, the Lord thy God is One; would that you knew them aright! As you interpret them, I seek in vain for their sense. It is said in the Psalms, God, Thy God, hath anointed Thee . Impress upon the reader’s mind the distinction between the Anointer and the Anointed; discriminate between the Thee and the Thy: make it clear to Whom and of Whom the words are spoken. For this definite confession is the conclusion of the preceding passage, which runs thus; Thy throne, O God, is for ever and ever; the sceptre of Thy kingdom is a right sceptre. Thou hast loved righteousness and hated iniquity. And then he continues, Therefore God, Thy God, hath anointed Thee . Thus the God of the eternal kingdom, in reward for His love of righteousness and hatred of iniquity, is anointed by His God. …

We have, then, adequately demonstrated that there is a God, and that His essence is incomprehensible. But that God is one and not many is no matter of doubt to those who believe in the Holy Scriptures. For the Lord says in the beginning of the Law: I am the Lord thy God, which have brought thee out of the land of Egypt. Thou shalt have no other Gods before Me . And again He says, Hear, O Israel, the Lord our God is one Lord . And in Isaiah the prophet we read, For I am the first God and I am the last, and beside Me there is no God. Before Me there was not any God, nor after Me will there be any God, and beside Me there is no God . And the Lord, too, in the holy gospels speaketh these words to His Father, And this is life eternal, that they may know Thee the only true God . But with those that do not believe in the Holy Scriptures we will reason thus.

55. Let us take them, then, in their order. In the Old Testament, to cite one out of a multitude of testimonies, it is written: “Before Me hath there been no other God, and after Me shall there be none.” I will not comment on this place, but ask thee straight: “Who speaks these words, the Father or the Son?” Whichever of the two thou sayest, thou wilt find thyself convinced, or, if a believer, instructed. Who, then, speaks these words, the Father or the Son? If it is the Son, He says, “Before Me hath there been no other God;” if the Father, He says, “After Me shall there be none.” The One hath none before Him, the Other none that comes after; as the Father is known in the Son, so also is the Son known in the Father, for whensoever you speak of the Father, you speak also by implication of His Son, seeing that none is his own father; and when you name the Son, you do also acknowledge His F …