Lesson 6: The Call to Take Up the Cross. Can you imagine telling Jesus what He should and shouldn’t do? Leave it to Peter to do just that. Before we judge Peter’s strong, opinionated objection to Jesus’ telling the disciples about His mission to Jerusalem, we need to understand the propensity of our own hearts to think that we know best. But the call of discipleship is the call to take up the cross and follow Jesus. In this lesson, Dr. Thomas explains the significance of Peter’s objection, why Jesus responded so strongly to Peter, and the weighty call to discipleship.