What does Matthew 26:50 mean?

The traitor Judas Iscariot (Matthew 26:14–16, 48) has done his work. He has led the crowd of soldiers and temple police to Jesus and has identified the One to be arrested with a kiss. Jesus does not resist. He calls Judas "friend," an especially cutting remark, since Judas is using pretended friendship to betray Jesus to His death. Rather than resist, Jesus simply tells Judas to go about his business.

Judas may have expected a fight, and not necessarily from Jesus. The disciples are armed (Luke 22:38) and Peter has declared his willingness to die for Christ (Luke 22:33). Jesus, for His part, makes no effort whatsoever to resist. Other gospel writers add details to the scene. John, especially, notes that Jesus is making a deliberate choice to make this an easy arrest. When they identified their target, He replied, "I am he" (John 18:4–6). They all fell to the ground, either out of fear or in response to some power that Jesus released in that moment.

Still, Jesus did not resist or run. He once more identified Himself and told the crowd of arresters to let those who were with Him go (John 18:8). Ignoring that advice is Peter (John 18:10), who will react with violence (Matthew 26:51).