Expositor's Bible Commentary Commentary John 13:27-28

"And after the sop, then entered Satan into him. Jesus therefore saith unto him, What thou doest, do quickly. Now no man at the table knew for what intent he spake this unto him." — John 13:27-28 (ASV)

(27a) “Satan entered into him.” This moment was Judas’s last opportunity to renounce his treachery. If the other disciples were ignorant of Judas’s intentions, he could change the course of his action without explanation, and none but Jesus would know. Once Judas left the room to seal his bargain with the priests, he would pass the point of no return.

(27b–28) Conscious that the time had come for his sacrifice (13:1), Jesus wished Judas to get on with his plot and leave. Once he was gone, Jesus would be able to continue his intimate ministry with his disciples in the upper room.