John 3:6

Clement of Alexandria Stromata Book III

Mysterium ergo hoc ad Christum et Ecclesiam ducit Apostolus: quemadmodum "quod ex carne generatur, caro est; ita quod ex spiritu, spiritus,"[146]

Tertullian On the Flesh of Christ

And (we have a proof of the same conclusion in the fact) that the Lord Himself sententiously and distinctly pronounced, "that which is born of the flesh is flesh,"[259]

Tertullian On the Flesh of Christ

was not suitable to Him. And then He adds, "That which is born of the Spirit is spirit,"[260]

Tertullian Against Praxeas

Learn then, together with Nicodemus, that "that which is born in the flesh is flesh, and that which is born of the Spirit is Spirit."[393]

Five Books in Reply to Marcion

From Spirit, life; "[109]

Hippolytus Refutation of All Heresies Book V

But what (is born) below is carnal, that is, he says, what is written. "That which is born of the flesh is flesh, and that which is born of the spirit is spirit."[67]

Hippolytus Dogmatical and Historical Fragments

in sooth, have been put in trust to give the account of His generation after the flesh; and are you then so bold as to seek the account (of His generation) after the Spirit, which the Father keeps with Himself, intending to reveal it then to the holy ones and those worthy of seeing His face? Rest satisfied with the word spoken by Christ, viz., "That which is born of the Spirit is spirit,"[280]

Seventh Council of Carthage Under Cyprian

And again, in the Gospel the Lord says: "That which is born of the flesh is flesh, and that which is born of the Spirit is spirit; because God is a Spirit, and he is born of God."[19]

The First Epistle of Clement Concerning Virginity

Every man with whom are these and such like things-every such man is of the flesh. For, "he that is born of the flesh is flesh; and he that is of the earth speaketh of the earth,"[75]