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.
Matthew 26
Matthew 26 is the 26th chapter of the Gospel of Matthew, part of the New Testament. This chapter covers the Jewish leaders' plot to kill Jesus, Judas Iscariot's agreement to betray Jesus to Caiphas, the Last Supper with the Twelve apostles and institution of the Eucharist, the agony in the garden of Gethsemane and the subsequent vindication of Jesus' predictions that one of the twelve will betray him and that he will be disowned by Peter.