In Sunday's Gospel reading, Peter takes Jesus aside one day to plead with him to stop all this talk about death and resurrection. He knew that some of Christ's followers might have been pretty close to the edge of leaving, dismayed, or at the very least confused, by Jesus' hard teachings (see John 6:60-70, for example). He just wanted to keep the ministry going, to keep the people involved. He wanted to make it easy for the people to keep following Jesus.