Peter confesses that Jesus is the “Christ, the Son of the Living God” in Matthew 16:16 and yet, four verses later, Peter rejects that Jesus would need to enter Jerusalem, die at the hand of the Pharisees and Scribes, and raise again. How can this firebrand disciple in one moment correctly identify and believe who Jesus is and yet in the next, reject the purpose for which the Christ came?
Augustine’s quote, “I believe in order to understand” might be a useful explanation. We are called to believe in the Christ and His Word so that we might gain understanding thereof. Peter, though he believed in the Christ, did not believe the Scriptures which were being explained to Him! Had Peter believed the Word, he would have identified the purpose for which Christ came and perhaps the Lord of Glory would have had zero need to call the disciple “Satan” and a “hindrance.”