Matthew 26:48

Even now do many fight against Jesus with spiritual weapons, to wit, with divers and shifting dogmas concerning God. It deserves enquiry why, when He was known by face to all who dwelt in Judæa, he should have given them a sign, as though they were unacquainted with His person. But a tradition to this effect has come down to us, that not only had He two different forms, one under which He appeared to men, the other into which He was transfigured before His disciples in the mount, but also that He appeared to each man in such degree as the beholder was worthy; in like manner as we read of the manna, that it had a flavour adapted to every variety of use, and as the word of God shows not alike to all. They required therefore a sign by reason of this His transfiguration.

Or, because whenever they had hitherto attempted to seize Him, He had escaped them they knew not how; as also He might then have done had He been so minded.

At any rate, "While He yet spake, lo, Judas, one of the twelve, came, and with him a great multitude with swords and staves, from the chief priests and elders of the people." Seemly surely are the instruments of the priests! "with swords and staves" do they come against Him! And Judas, it is said, with them, one of the twelve. Again he calleth him "of the twelve," and is not ashamed. Now he that betrayed Him gave them a sign, saying, "Whomsoever I shall kiss, that same is He, hold Him fast." Oh! what depravity had the traitor's soul received. For with what kind of eyes did he then look at his Master? with what mouth did he kiss Him? Oh! accursed purpose; what did he devise? What did he dare? What sort of sign of betrayal did he give? Whomsoever I shall kiss, he saith. He was emboldened by his Master's gentleness, which more than all was sufficient to shame him, and to deprive him of all excuse for that he was betraying one so meek.

(non occ.) Having said above that the Lord offered Himself of His own accord to His pursuers, the Evangelist proceeds to relate how He was seized by them.

(Serm. de Symb. ad Catech. 6.) Exult, Christian, you have gained by this bargain of your enemies; what Judas sold, and what the Jews bought, belongs to you.