John 6:70,71 - Joseph Benson’s Commentary on the Old and New Testaments

Jesus answered them And, yet even ye have not all acted, nor will you act, suitably to this knowledge and faith. For, have I not chosen, or elected, you twelve To the honour and happiness of a peculiar intimacy with me, and to a station of the most distinguished eminence and importance in my church? And yet one of you, as I well know, is a devil Is now influenced by one, and will become my accuser and betrayer. As the word διαβολος, rendered devil, sometimes signifies a false accuser, Mr. Locke considers our Lord as intimating here, that the reason why he had not more plainly declared himself to be the Messiah, was, because he knew Judas would, on that ground, have accused him of rebellion against the Romans. But, as Dr. Doddridge observes, “there does not appear to be any proof that Judas from the beginning intended to betray Christ. It is more than probable, that he at first engaged with him in expectation of secular advantages, and finding those views disappointed, he might now begin to form that detestable scheme which he afterward executed. If this was the occasion on which he first entertained the thought, as it probably might be, one would imagine that such an intimation of his secret wickedness must have struck him to the heart.” He spake of Judas Iscariot, the son of Simon He meant Judas, though he did not at this time think fit to name him. Christ called Judas a devil, because he foresaw that he would be an apostate and a traitor. So likewise in rebuking Peter, who had expressed an utter aversion to his suffering at Jerusalem, he called him Satan, on account of that one act, by which he opposed the great design of his coming into the world. And he might much more give Judas the name of devil, who resembled Satan so nearly, in the wickedness of his dispositions and actions.