John Lightfoot on Matthew 10:4

[Simon the Canaanite.] In Luke it is Zealot. See who are called Zealots in Josephus. Of whose sect, if you should say this Simon was before his conversion, perhaps you would do him no more wrong than you would do his brother Matthew, when you should say that he was a publican.

[Iscariot.] It may be inquired whether this name was given him while he was alive, or not till after his death. If while he was alive, one may not improperly derive it from Skortja, which is written also Iskortja: where, while the discourse is of a man vowing that he would not use this or that garment, we are taught these things;..."These are garments, some, of leather, and some of a certain kind of clothing." The Gemara asketh, "What is Iskortja? Bar Bar Channah answered, A Tanner's garment" The Gloss is, "A leathern apron that tanners put on over their clothes." So that Judas Iscariot may perhaps signify as much as Judas with the apron. But now in such aprons they had purses sewn, in which they were wont to carry their money, as you may see in Aruch...which we shall also observe presently. And hence, it may be, Judas had that title of the purse-bearer, as he was called Judas with the apron.

Or what if he used the art of a tanner before he was chose into discipleship? Certainly we read of one Simon a tanner, Acts 9:43; and that this Judas was the son of Simon, John 12:4.

But if he were not branded with this title till after his death, I should suppose it derived from Iscara: which word what it signifies, let the Gemarists speak: "Nine hundred and three kinds of death were created in the world, as it is said, and the issues of death, Psalm 68:21. The word issues arithmetically ariseth to that number. Among all those kinds, Iscara is the roughest death..." Where the Gloss is, 'Iscara' in the mother-tongue is estrangulament. By learned men for the most part it is rendered angina, the quinsy. The Gemara sets out the roughness of it by this simile, "The Iscara is like to branches of thorns in a fleece of wool; which if a man shake violently behind, it is impossible but the wool will be pulled off by them." It is thus defined in the Gloss, 'The Iscara' begins in the bowels, and ends in the throat. See the Gemara there.

When Judas therefore perished by a most miserable strangling, being strangled by the devil (which we observe in its place), no wonder if this infamous death be branded upon his name, to be commonly styled Judas Iscariot, or 'that Judas that perished by strangling.'

[Who also betrayed him.] Let that of Maimonides be observed: "It is forbidden to betray an Israelite into the hands of the heathen, either as to his person, or as to his goods," &c. "And whosoever shall so betray an Israelite shall have no part in the world to come." Peter spake agreeably to the opinion of the nation, when he said concerning Judas, "He went unto his own place," Acts 1:25. And so doth Baal Turim concerning Balaam; "'Balaam went to his place,' Numbers 24:25; that is (saith he), he went down to hell."