Ver. 15,16. Mark saith, Mar_8:29, Thou art the Christ. Luke saith, Luk_9:20, Peter answering said, The Christ of God, that is, the Messiah. You that are my disciples and apostles, what is your opinion of me? Our Lord expects not only faith in our hearts, but the confession of our lips, Rom_10:10.
And Simon Peter answered, not because he had any priority amongst the apostles, but he was of a more quick and fervid temper than the rest, and so speaketh first; they silently agreed to what he said. What he saith is but little, but of that nature that it is the very foundation of the gospel.
Thou art Christ, the Anointed, the person of old promised to the world under the name of the Messiah, Dan_9:25,26.
The Son, not by adoption, but by nature for they believed John the Baptist, Elias, and the old prophets the sons of God by grace. It is plain Peter means more than that.
Of the living God. Our Lord had asked, Whom do men say that I the Son of man am? And in the same sense he speaks to the disciples, Whom do ye say that I the Son of man am? Lord, saith Peter, we believe that thou the Son of man
art the Christ, the Son of the living God. God is often in Scripture called the living God, in opposition to idols, which had eyes and saw not, ears and heard not, nor had any life in them, Gen_16:13Heb_3:12 9:14 &c. So as here we have a full and plain confession of that doctrine, which is the foundation of the gospel.