Luke: Twice in this reading Jesus warns Peter that he will need to “turn back” (v. 32). One doesn’t turn back unless one has already turned away. I.e., repentance. In the next verse Jesus is perfectly clear that Peter will deny Him before morning (something about a cock crowing). Notice back in verse 31 that Jesus says, “Simon, Simon, Satan has asked to sift all of you.” So it was not just Peter who was a target of Satan but all of them. Care to guess which one Satan won over.
Gospel: Luke 22:31-38
New Testament: 2 Thess. 3:6 -18
Old Testament: Isaiah 8:1-15