For Jesus had known from the beginning which of them did not believe and who would betray him (v. 64)
“Have I not chosen you, the Twelve? Yet one of you is a devil!” (v. 70)
He meant Judas, the son of Simon Iscariot, who, though one of the Twelve, was later to betray him (v. 71)
Jesus knew who it was “from the beginning,” according to verse 64. He chose the twelve and knew well that one of them was “a devil.” He spoke of Judas Iscariot, “who, though one of the Twelve, was later to betray him.”
Jesus knew it and had dealt it with it a while. We see in John 12 that the objection of the anointing of Jesus at Bethany is limited to Judas in John’s version. Unlike other gospels, Judas is the singular objector here and John is quick to point out his character here, saying: He did not say this because he cared about the poor but because he was a thief; as keeper of the money bag, he used to help himself to what was put into it. (John 12:6, NIV).” John even denotes him, in verse 5, as “Judas Iscariot, who was later to betray him.”
The Bible is full of bits and pieces about betrayal, especially by those who are said to be close to us. David says that he could have handled a stranger betraying him, but it was a friend, a “man my equal.” The prophecy of Zechariah points out that Jesus was betrayed for thirty pieces of silver. Isaiah presents the “man of sorrows” to the believer as the suffering and sacrificial Savior. James simply said for us to submit to the Lord and that the devil would flee from us.
We have to understand that these show us that we can withstand the devil’s attacks. Just as Jesus withstood him during the temptation presented in the wilderness, we can withstand the fiery darts of the devil as he attacks us from all sides. We can put on the whole armor of God, as it is written in Ephesians chapter 6, and have our defenses girded up against the enemy.