Dialogue with Trypho: Chapter 48
Trypho: We have heard what you think of these matters. Resume the discourse where you left off, and bring it to an end. For some of it appears to me to be paradoxical, and wholly incapable of proof. For when you say that this Christ existed as God before the ages, then that He submitted to be born and become man, yet that He is not man of man, this [assertion] appears to me to be not merely paradoxical, but also foolish.
Justin: I know that the statement does appear to be paradoxical, especially to those of your race, who are ever unwilling to understand or to perform the [requirements] of God, but [ready to perform] those of your teachers, as God Himself declares. Isaiah 29:13 Now assuredly, Trypho, [the proof] that this man is the Christ of God does not fail, though I be unable to prove that He existed formerly as Son of the Maker of all things, being God, and was born a man by the Virgin. But since I have certainly proved that this man is the Christ of God, whoever He be, even if I do not prove that He pre-existed, and submitted to be born a man of like passions with us, having a body, according to the Father's will; in this last matter alone is it just to say that I have erred, and not to deny that He is the Christ, though it should appear that He was born man of men, and [nothing more] is proved [than this], that He has become Christ by election. For there are some, my friends, of our race, who admit that He is Christ, while holding Him to be man of men; with whom I do not agree, nor would I, even though most of those who have [now] the same opinions as myself should say so; since we were enjoined by Christ Himself to put no faith in human doctrines, but in those proclaimed by the blessed prophets and taught by Himself.
☝ There we are!