Andrew, Simon Peter’s brother, was one of the two who heard John’s witness and followed Jesus. The first thing he did after finding where Jesus lived was find his own brother, Simon, telling him, “We’ve found the Messiah” (that is, “Christ”). He immediately led him to Jesus.
Jesus took one look up and said, “You’re John’s son, Simon? From now on your name is Cephas” (or Peter, which means “Rock”).