Luke 9:18, 19, 20, 21

Once when Jesus was praying in solitude, and the disciples were with him, he asked them, “Who do the crowds say that I am?”

They said in reply, “John the Baptist; others, Elijah; still others, ‘One of the ancient prophets has arisen.’”

Then he said to them, “But who do you say that I am?” Peter said in reply, “The Messiah of God.”

He rebuked them and directed them not to tell this to anyone. The First Prediction of the Passion.