Augustine Confessions 10:68

Chapter XLIII.—That Jesus Christ, at the Same Time God and Man, is the True and Most Efficacious Mediator.

68. But the true Mediator, whom in Thy secret mercy Thou hast pointed out to the humble, and didst send, that by His example also they might learn the same humility—that “Mediator between God and men, the man Christ Jesus,” appeared between mortal sinners and the immortal Just One—mortal with men, just with God; that because the reward of righteousness is life and peace, He might, by righteousness conjoined with God, cancel the death of justified sinners, which He willed to have in common with them. Hence He was pointed out to holy men of old; to the intent that they, through faith in His Passion to come, even as we through faith in that which is past, might be saved. For as man He was Mediator; but as the Word He was not between, because equal to God, and God with God, and together with the Holy Spirit one God.