John Chrysostom

Where it is evident that He did not proclaim him openly to all, lest He should make him the more shameless; at the same time He did not altogether keep it silent, lest thinking that he was not discovered, he should boldly hasten to betray Him.

Catena Aurea by Aquinas ↗

Theophylact of Ohrid

How then were they reclining, when the Law commanded that the Passover be eaten standing? One must think that the Lord first performed the Passover according to the Law, and then reclined in order to impart His own Passover. The disciples began to grieve when the Lord said: "one of you will betray Me." Although they were free from this sin, they were nevertheless troubled, for they believed God, who knows their hearts, more than they believed themselves.

Commentary on Mark ↗

Cyprian

His wonderful patience is seen in the way he dealt with his disciples. He was even able to tolerate Judas to the end with enduring patience. He could eat calmly with his betrayer. He could patiently be aware of his enemy at his own table and not let on. He did not even refuse the kiss of the traitor.

Treatise IX. On the Advantage of Patience 6 ↗