"But the boat was now in the middle of the sea, tossed by the waves, for the wing was contrary. Now in the fourth watch of the night Jesus went to them, walking on the sea. And when the disciples saw Him walking on the sea, they were troubled, saying "It is a ghost!" And they cried out in fear.
But immediately Jesus spoke to them saying, "Be of good cheer! It is; do not be afraid".
And Peter answered Him and said, "Lord if it is You, command me to come to You on the water".
So He said, "Come".
And when Peter had come down out of the boat he walked on the water to go to Jesus. But when he saw the the wind was boisterous he was afraid; and beginning to sink he cried out, "Lord, save me!".
And immediately Jesus stretched out His hand and caught him and said to him, "O you of little faith, why did you doubt?"
And when they got into the boat the wind ceased. Then those who were in the boat came and worshipped Him saying, "Truly You are the Son of God"."
(Matthew 14: 24-33)