Was Judas at the Last Supper?

Answer:

Let's go through the accounts, trying to put them in chronological order:

Matthew and Mark tell us that Judas made a deal with the chief priests before the Passover supper (Matthew 26:14-18; Mark 14:10-11). He was just waiting for a good time to do it.

The last supper memorial was established during the Passover meal (Luke 22:14-20).

John tells us that Judas Iscariot had already planned to betray Jesus before the Passover supper. "And supper being ended, the devil having already put it into the heart of Judas Iscariot, Simon's son, to betray Him" (John 13:2). Luke tells us that Jesus said his betrayer was at the table (Luke 22:22-23).

Jesus then washes the feet of his disciples (John 13:3-20). Luke tells us why: the disciples were arguing once again about who would be the greatest in the kingdom (Luke 22:24-27). Returning to the table, he again tells his disciples that one of them would betray him (John 13:21). This caused a stir among the disciples, wondering who was planning such a thing (John 13:22-24). Finally, they got John to ask Jesus who it was "Jesus answered, "It is he to whom I shall give a piece of bread when I have dipped it." And having dipped the bread, He gave it to Judas Iscariot, the son of Simon" (John 13:26).

At this point, Judas decided to follow through with his plan. "Now after the piece of bread, Satan entered him. Then Jesus said to him, "What you do, do quickly." But no one at the table knew for what reason He said this to him. For some thought, because Judas had the money box, that Jesus had said to him, "Buy those things we need for the feast," or that he should give something to the poor. Having received the piece of bread, he then went out immediately. And it was night" (John 13:27-30).

Both Matthew and Mark's accounts discuss the betrayal and how the betrayer would be identified (Matthew 26:20-25; Mark 14:17-21) before discussing the Last Supper (Matthew 26:26-29; Mark 14:22-25). Notice that both events are said to happen during the Passover supper (Matthew 26:20-21, 26; Mark 14:18, 22), but neither Matthew or Mark's accounts claim what order the events occurred. It appears there were two discussions about the betrayal and these two authors chose to combine the topics (something Matthew does frequently) rather than follow strict time-order.

Luke stated at the beginning that he was presenting a chronological account of the events in Jesus' life (Luke 1:3). John's account gives us a time frame by telling us that the identifying of the betrayer came at the end of the supper.