Matthew 26:25
ESV - 25 Judas, who would betray him, answered, "Is it I, Rabbi?" He said to him, "You have said so.
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Each man must choose what action to pursue. Jesus spoke truth to his disciples and then invited them to partake of the tokens of his body-bread and wine. Jesus did not have to stop Judas from doing anything. Neither does Jesus or any wise disciple have to stop anyone from partaking of the emblems. Give them instead the word: He that partakes unworthily brings damnation on himself. If a man chooses to rebel against the word of God, he is a fool and the pestle mortar treatment of Proverbs 27:22 will not help either. He will quickly listen up one day when he sinks into the manhole of Revelation 21:8, but it will be way too late!