Tractates on the Gospel of John

¹⁰ “These things were done in Bethany, beyond Jordan, where John was baptizing. The next day John saw Jesus coming unto him, and says, Behold the Lamb of God; behold Him who takes away the sin of the world!” Let no one so arrogate to himself as to say that he takes away the sin of the world. Give heed now to the proud men at whom John pointed the finger. The heretics were not yet born, but already were they pointed out; against them he then cried from the river, against whom he now cries from the Gospel.

Jesus comes, and what says he? “Behold the Lamb of God!” If to be innocent is to be a lamb, then John was a lamb, for was not he innocent? But who is innocent? To what extent innocent? All come from that branch and shoot, concerning which David sings, even with groanings, “Behold, I was shapen in iniquity; and in sin did my mother conceive me.” Alone, then, was He, the Lamb who came, not so. For He was not conceived in iniquity, because not conceived of mortality; nor did His mother conceive Him in sin, whom the Virgin conceived, whom the Virgin brought forth; because by faith she conceived, and by faith received Him.

Therefore, “Behold the Lamb of God.” He is not a branch derived from Adam: flesh only did he derive from Adam, Adam's sin He did not assume. He who took not upon Him sin from our lump, He it is who takes away our sin. “Behold the Lamb of God, who takes away the sin of the world!”