The following article is excerpted from the International Standard Bible Encyclopedia, which is in the public domain.
He was the son of Simon (John 13:2) or Simon Iscariot (John 6:71; 13:26), the meaning of Iscariot explaining why it was applied to his father also. The first Scriptural reference to Judas is his election to the apostleship (compare Matthew 10:4; Mark 3:19; Luke 6:16). He may have been present at the preaching of John the Baptist at Bethany beyond Jordan (compare John 1:28), but more probably he first met Jesus during the return of the latter through Judea with His followers (compare John 3:22). According to the Gospel of the Twelve Apostles, Judas was among those who received the call at the Sea of Tiberias (compare Matthew 4:18-22).
Before the Betrayal
For any definite allusion to Judas during the interval lying between his call and the events immediately preceding the betrayal, we are indebted to John alone. These allusions are made with the manifest purpose of showing forth the nefarious character of Judas from the beginning; and in their sequence there is a gradual development and growing clearness in the manner in which Jesus makes prophecy regarding his future betrayer. Thus, after the discourse on the Bread of Life in the synagogue of Capernaum (John 6:26-59), when many of the disciples deserted Jesus (John 6:66) and Peter protested the allegiance of the apostles (John 6:69), Jesus answered, "Did not I choose you the twelve, and one of you is a devil" (John 6:70). Then follows John's commentary, "Now he spake of Judas the son of Simon Iscariot, for he it was that should betray him, being one of the twelve" (John 6:71), implying that Judas was already known to Jesus as being in spirit one of those who "went back, arid walked no more with him" (John 6:66).
But the situation, however disquieting it must have been to the ambitious designs which probably actuated Judas in his acceptance of the apostleship (compare below), was not sufficiently critical to call for immediate desertion on his part. Instead, he lulled his fears of exposure by the fact that he was not mentioned by name, and continued ostensibly one of the faithful. Personal motives of a sordid nature had also influence in causing him to remain. Appointed keeper of the purse, he disregarded the warnings of Jesus concerning greed and hypocrisy (compare Matthew 6:20; Luke 12:1-3) and appropriated the funds to his own use. As a cloak to his avarice, he pretended to be zealous in their administration, and therefore, at the anointing of Jesus' feet by Mary, he asked "Why was not this ointment sold for 300 shillings, and given to the poor? Now this he said, not because he cared for the poor; but because he was a thief, and having the bag took away what was put therein" (John 12:5,6; compare also Matthew 26:7-13; Mark 14:3-8).
Before the Betrayal
Yet, although by this craftiness Judas concealed for a time his true nature from the rest of the disciples, and fomented any discontent that might arise among them (compare Mark 14:4), he now felt that his present source of income could not long remain secure. The pregnant words of his Master regarding the day of his burial (compare Matthew 26:12; Mark 14:8; John 12:7) revealed to His betrayer that Jesus already knew well the evil powers that were at work against Him; and it is significant that, according to Mt and Mk, who alone of the synoptists mention the anointing, Judas departed immediately afterward and made his compact with the chief priests (compare Matthew 26:14,15; Mark 14:10,11; compare also Luke 22:3-6). But his absence was only temporary.
He was present at the washing of the disciples' feet, there to be differentiated once more by Jesus from the rest of the Twelve (compare "Ye are clean, but not all" and "He that eateth my bread lifted up his heel against me," John 13:10,18), but again without being named. It seemed as if Jesus wished to give Judas every opportunity, even at this late hour, of repenting and making his confession. For the last time, when they had sat down to eat, Jesus appealed him thus with the words, "One of you shall betray me" (Matthew 26:21; Mark 14:18; Luke 22:21; John 13:21). And at the end, in answer to the anxious queries of His disciples, "Is it I?" He indicated his betrayer, not by name, but by a sign:
"He it is, for whom I shall dip the sop, and give it him" (John 13:26). Immediately upon its reception, Judas left the supper room; the opportunity which he sought for was come (compare John 13:30; Matthew 26:16). There is some doubt as to whether he actually received the eucharistic bread and wine previous to his departure or not, but most modern commentators hold that he did not. On his departure, Judas made his way to the high priests and their followers, and coming upon Jesus in the Garden of Gethsemane, he betrayed his Master with a kiss (Matthew 26:47-50; Mark 14:43,44; Luke 22:47; John 18:2-5).
After His Death
After the betrayal, Mk, Lu and Joh are silent as regards Judas, and the accounts given in Mt and Ac of his remorse and death vary in detail. According to Mt, the actual condemnation of Jesus awakened Judas' sense of guilt, and becoming still more despondent at his repulse by the chief priests and elders, "he cast down the pieces of silver into the sanctuary, and departed; and he went away and hanged himself." With the money the chief priests purchased the potter's field, afterward called "the field of blood," and in this way was fulfilled the prophecy of Zechariah (11:12-14) ascribed by Matthew to Jeremiah (Matthew 27:3-10).
The account given in Acts 1:16-20 is much shorter. It mentions neither Judas' repentance nor the chief priests, but simply states that Judas "obtained a field with the reward of his iniquity; and falling headlong, he burst asunder in the midst, and all his bowels gushed out" (1:18). The author of Ac finds in this the fulfillment of the prophecy in Psalms 69:25. The Vulgate (Jerome's Latin Bible, 390-405 A.D.) rendering, "When he had hanged himself, he burst asunder," suggests a means of reconciling the two accounts.
International Standard Bible Encyclopedia