it hurts

21 After saying these things, Jesus was troubled in his spirit, and testified, “Truly, truly, I say to you, one of you will betray me.” 
John 13:21 

Jesus was betrayed and it hurt. Even though he knew it was going to happen, it hurt. Betrayal hurts, betrayal by a friend hurts. If you have experienced this, Jesus knows how it feels and you can draw near to him to receive mercy and grace.

For we do not have a high priest who is unable to sympathize with our weaknesses, but one who in every respect has been tempted as we are, yet without sin. Let us then with confidence draw near to the throne of grace, that we may receive mercy and find grace to help in time of need.
(Hebrews 4:15-16)