The emphasis of the Greek construction is, “But you, who do you say that I am?” For a somewhat similar conversation between Jesus and His disciples see John 6:66-69. Constant companions of Jesus now for more than a year, and some of them for more than two years, the disciples had had opportunities to observe the many evidences of the divinity of Jesus (see on John 1:1-3) far exceeding those of other men. Now Jesus gave them an opportunity to testify to their faith. Though their understanding of Him was even yet far from perfect, Andrew, Philip, and Nathanael had apparently believed from the very beginning that Jesus was the Messiah (see John 1:40-49; DA 141). After the storm on the lake all the disciples had worshiped Him (see on Matt. 14:33), and after the crisis in Galilee they had professed faith in Him as the Son of God (John 6:68, 69).