John Calvin Commentary John 6:70

"Jesus answered them, Did not I choose you the twelve, and one of you is a devil?" — John 6:70 (ASV)

Jesus answered them. Since Christ replies to all, we infer from it that all spoke by the mouth of Peter. Besides, Christ now prepares and fortifies the eleven apostles against a new offense which was already at hand. It was a powerful instrument of Satan for shaking their faith when they were reduced to so small a number. The fall of Judas might take away all their courage, for since Christ had chosen that sacred number, who would ever have thought that any portion of the whole number could be torn away?

That admonition of Christ may be interpreted this way: “You twelve alone remain out of a large company. If your faith has not been shaken by the unbelief of many, prepare for a new contest, for this company, though small, will be still diminished by one man.”

Have not I chosen you twelve? When Christ says that he has chosen or elected twelve, he does not refer to the eternal purpose of God, for it is impossible that any one of those who have been predestined to life shall fall away. However, having been chosen to the apostolic office, they ought to have surpassed others in piety and holiness. He used the word chosen, therefore, to denote those who were eminent and distinguished from the ordinary rank.

And one of you is a devil. He unquestionably intended, by this name, to hold up Judas to the utmost detestation. For those who extenuate the atrocity implied in the name are mistaken, and indeed, we cannot sufficiently execrate those who dishonor so sacred an office. Teachers who faithfully discharge their office are called angels.

They should seek the law at his mouth, for he is the angel of the Lord of Hosts,
(Malachi 2:7).

Justly, therefore, is he accounted a devil who, after having been admitted to so honorable a rank, is corrupted through his treachery and wickedness.

Another reason is that God allows more power and liberty to Satan over wicked and ungodly ministers than over other ordinary men. Therefore, if those who were chosen to be pastors are driven by diabolical rage, so as to resemble wild and monstrous beasts, we are so far from being entitled on that account to despise the honorable rank to which they belong, that we ought rather to honor it the more, when its profanation is followed by so fearful a punishment.