Did Peter always believe that Jesus was the Christ?
Peter first met Jesus because his brother told him that they had found the Messiah (John 1:41-42). We are not told if Peter was immediately convinced or not, but we do know that Peter became a staunch follower of Jesus. It was Peter who stated, "You are the Christ, the Son of the living God" (Matthew 16:16). It was also Peter who said on another occasion, "Lord, to whom shall we go? You have the words of eternal life. Also we have come to believe and know that You are the Christ, the Son of the living God" (John 6:68-69).
It is also clear from the gospels that Peter did not always understand exactly what it meant for Jesus to be the Christ. He had his moments of doubt and he was sometimes at odds with Jesus, especially over the necessity of Jesus' death.