Judas Iscariot
There are several explanations as to why Judas betrayed Jesus. In the earliest account, in the Gospel of Mark, when he goes to the chief priests to betray Jesus, he is offered money as a reward, but it is not clear that money is his motivation. In the Gospel of Matthew account, on the other hand, he asks what they will pay him for handing Jesus over. In the Gospel of Luke and the Gospel of John, the devil enters into Judas, causing him to offer to betray Jesus. The Gospel of John account has Judas complaining that money has been spent on expensive perfumes to anoint Jesus which could have been spent on the poor, but adds that he was the keeper of the apostles' purse and used to steal from it.
Rejection of Jesus
Jesus is rejected in Judaism as a failed Jewish Messiah claimant and a false prophet by most Jewish denominations. However, Messianic Jewish congregations like Jews for Jesus have made the case that he is the Messiah promised by the Torah and the Prophets. On the Jewish side, the accounts of Jewish rejection of Jesus are prominently featured in the Birkat haMinim of the Amidah and the Talmud. The Talmud indicates that Rabbi Gamaliel II directed Samuel ha-Katan to write another paragraph for the central Amidah-prayer, inveighing against (early Christian) informers and heretics, which was inserted as the twelfth paragraph in modern sequence (Birkat haMinim).