John Gill

And after the sop, Satan entered into him,.... After he had taken and eaten the sop, or crust of bread, by which he was pointed out to be the betrayer, "Satan entered into him"; possessed his body, and filled his mind, and stirred him up more eagerly to pursue with rigour his wicked design. The Jews have a saying (l), that "no man commits a transgression, until , "a spirit of madness enters into him".'' Such an evil spirit entered into Judas, which pushed him on to commit this horrid iniquity: then said Jesus to him, that thou doest, do quickly; this he said, not as approving his wicked design, and exhorting him to it as a laudable action, but rather as deriding him, having nothing to care about, or fear from him; or as upbraiding him with his perfidy and wickedness, and signifying that he should take no methods to prevent him, though he fully knew what was in his heart to do; and it seems also to express the willingness of Christ, and his eager and hearty desire to suffer and die for his people, in order to obtain salvation for them. (l) T. Bab. Sota, fol. 3. 1. Tzeror Hammor, fol. 112. 1. & 117. 3.