On the day before his crucifixion, Jesus gathered his apostles into an upper room in Jerusalem. After washing their feet, he predicted that one of them would betray him.
After Judas left, he declared that he himself would soon leave them, and that Peter would deny him three times. It is no wonder, then, that the remaining apostles were unsettled by what had just occurred.
Jesus comforted his apostles by saying, “Let not your heart be troubled; ye believe in God, believe also in me (John 14:1).”