The declaration by Peter that Jesus was Christ, the Son of the Living God, was not the end of it. We need to read further because in the next couple of verses, Jesus gives Peter a task and a responsibility. That same responsibility falls to everyone who accepts that Jesus is indeed the Son of God.
Often we fall short of our responsibility of living the Gospel and merely talk about it. And sharing means living it. You do not preach the Gospel by singing “Jesus songs” inside church and then going out and living selfishly.
“By this shall all men know that ye are my disciples, if ye have love one to another.” John 13: 35
Source: Daily Sabbath School Lessons