During the Last Supper, Jesus reveals that one of the disciples will betray Him. Judas leaves the meal early to arrange the betrayal.
Scriptural References: Matthew 26:21-25 - Jesus announces that one of the disciples will betray Him, and Judas is identified as the one who will betray Him. John 13:21-30 - Jesus identifies Judas as the betrayer, and Judas leaves to carry out his plan.