Robertson's Word Pictures of the New TestamentMatthew 16:16
Peter is the spokesman now: "Thou art the Christ, the Son of the living God" (Su ei o Xristov o uiov tou teou tou zwntov). It was a noble confession, but not a new claim by Jesus. Peter had made it before (John 6:69) when the multitude deserted Jesus in Capernaum. Since the early ministry (John 4) Jesus had avoided the word Messiah because of its political meaning to the people. But now Peter plainly calls Jesus the Anointed One, the Messiah, the Son of the God the living one (note the four Greek articles). This great confession of Peter means that he and the other disciples believe in Jesus as the Messiah and are still true to him in spite of the defection of the Galilean populace (John 6).