John 1:6

Irenaeus Against Heresies Book III

The same came as a witness, that he might bear witness of that Light. He was not that Light, but [came] that he might testify of the Light."[128]

Clement of Alexandria Stromata Book III

Si autem in luce ambulamus, sicut et ipse est in luce, societatem habemus cum ipso, et sanguis Jesu filii ejus emundat nos a peccato."[25]

Tertullian On Baptism

celestial in John-the Spirit of prophecy-so completely failed, after the transfer of the whole Spirit to the Lord, that he presently sent to inquire whether He whom he had himself preached,[105]

Origen Commentary on John Book II

And again that darkness is brought upon men by their evil deeds, we learn from John himself, when he says in his epistle,[73]

Origen Commentary on John Book II "There was a man sent from God, whose name was John."[89]