John the Apostle
John 6:70BSB·traditional attribution

Jesus answered them, “Have I not chosen you, the Twelve? Yet one of you is a devil!”

John Calvin Reformed @genevareformer

70. Jesus answered them. Since Christ replies to all, we infer from it that all spake 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, but the fall of Judas might...

Matthew Henry Presbyterian @wholebiblehenry

We have here an account of the effects of Christ's discourse. Some were offended and others edified by it; some driven from him and others brought nearer to him. I. To some it was a savour of death unto death; not only to the Jews, who were professed enemies to him and his doctrine, but even to many of his disciples, such as were disciples...

Commenting on John 6:60-71

Albert Barnes Presbyterian @notesbybarnes

Verse 70. Have not I chosen you twelve? There is much emphasis in these words. Have not I--I, the Saviour, the Messiah, chosen you in mercy and in love, and therefore it will be a greater sin to betray me? Chosen. Chosen to the apostolic office; conferred on you marks of peculiar favour, and treason is therefore the greater sin. You twelve. So small a number.