mark 14:10 And Judas Iscariot, one of the twelve, went unto the chief priests, to betray him unto them. - Free Bible Online

      10. And Judas Iscariot, one of the twelve, went unto the chief priests, to betray him unto them--that is, to make his proposals, and to bargain with them, as appears from Matthew's fuller statement (Mt 26:14, 15) which says, he "went unto the chief priests, and said, What will ye give me, and I will deliver Him unto you? And they covenanted with him for thirty pieces of silver." The thirty pieces of silver were thirty shekels, the fine paid for man- or maid-servant accidentally killed (Ex 21:32), and equal to between four and five pounds sterling--"a goodly price that I was prized at of them!" (Zec 11:13).

JFB.