When it was evening, he reclined with the twelve. And as they were eating, he said, "Truly, I say to you, one of you will betray me." And they were very sorrowful and began to say to him one after another, "Is it I, Lord?" He answered, "He who has dipped his hand in the dish with me will betray me."...Judas, who would betray him, answered, "Is it I, Rabbi?" He said to him, "You have said so." Matt. 26:20-25, ESV.
If Jesus had startled His followers by taking the towel and washing their feet, His announcement that one of them would betray Him was shock on steroids.
Prior to that Thursday evening He had indicated that He would die. But never has He tied one of the disciples to that event. For the first time He now states that a member of His own inner circle will play the part of betrayer. The effect on the twelve is traumatic. Matthew 26:22 tells us that they were "exceeding sorrowful" (KJV), "in great distress" (NEB), or "deeply grieved" (NASB). No matter how one translates the Greek, it reflects violent emotion and shock.
The revelation shakes up the disciples even to the point of self-doubt. Each in turn inquires, "Is it I, Lord?" And each expects a negative reply, as indicated by the New International Version's rendering: "Surely you don't mean me, Lord?" (verse 22).
It is of interest to note that Judas must have covered his tracks quite carefully. After all, no one asks, "Is it Judas?" Yet Judas knows. Caught off guard, he does not immediately join with the other disciples in inquiring if it is him. But he soon comes to his senses, realizing that if he fails to participate in the query it will identify him as the culprit. Thus he also says, "Is it I, Rabbi?" Note that Judas does not refer to Jesus as "Lord," as do the other disciples, but rather as "Rabbi"--a term of address appropriate for any Jewish teacher and one not used at all by the other disciples in the first Gospel.
Jesus does not respond to the question of the other disciples, but He indicates to Judas His awareness that He will indeed be the betrayer. At that point Judas realizes that he has been found out. He also knows that he will have to act quickly if he is to successfully carry out his plan. It is about this time, John tells us, that "Satan entered into" Judas. Jesus told him that what he had to do should be done "quickly," and Judas "went immediately out" to put his plan into action (John 13:27-30).
We find a lesson even in this sad story. The church has never been pure. It has never existed with all of its members born-again Christians. We need to keep courage when even leaders fall by the way or turn against the faith.