Gregory the Great — as excerpted in the Catena Aurea on John 8:44-47

“(Hom. xviii. in Evang.) Observe here the condescension of God. He who by virtue of His Divinity could justify sinners, deigns to shew from reason, that He is not a sinner. It follows: He that is of God heareth God’s words; ye therefore hear them not, because ye are not of God.”