John Calvin Commentary John 8:38

"I speak the things which I have seen with [my] Father: and ye also do the things which ye heard from [your] father." — John 8:38 (ASV)

I speak what I have seen with my Father. He had already made frequent mention of his Father; and now, by an argument drawn from contrary things, he infers that they are enemies to God and are the children of the devil because they oppose his doctrine. “For my part,” he says, “I bring nothing forward but what I have learned from my Father.”

How is it then that the word of God provokes you to such fury, if not because you have an opposite father?” He says that he speaks, and they do, because he fulfilled the role of a teacher, while they worked strenuously to extinguish his doctrine. At the same time, he protects the Gospel against contempt by showing that it is not surprising if it is opposed by the children of the devil. Instead of you do, some render it, “Do you what you have seen with your father”; as if Christ had said, “Come, show that you are the children of the devil by opposing me; for I speak nothing but what God has commanded.”