Matthew 14:28-36

And Peter answered him, “Lord, if it is you, command me to come to you on the water.” He said, “Come.” So Peter got out of the boat and walked on the water and came to Jesus. But when he saw the wind, he was afraid, and beginning to sink he cried out, “Lord, save me.” Jesus immediately reached out his hand and took hold of him, saying to him, “O you of little faith, why did you doubt?” And when they got into the boat, the wind ceased. And those in the boat worshiped him, saying, “Truly you are the Son of God.” And when they had crossed over, they came to land at Gennesaret. And when the men of that place recognized him, they sent around to all that region and brought to him all who were sick and implored him that they might only touch the fringe of his garment. And as many as touched it were made well.

land at Gennesaret - NW of the Sea of Galilee — on the plain northwest of the Sea of Galilee between Capernaum and Tiberias

"Christ explained the reason that Peter began to sink. Peter had obeyed the command of Christ. He had begun the walk by faith. But the fact that he began his walk by exercising faith did not mean that he could stop walking by faith. When Peter ceased to walk by faith, even though in the will of God and in the presence of Christ, he began to sink. Christ brought Peter to the boat, and it was then that 'the wind died down' (Matthew 14:32). Those in the boat had seen Christ walk on the water. They had seen Peter walk on the water, and they had seen Christ rescue and restore Peter when he failed in his walk by faith. Now their response was to cry out, 'Truly you are the Son of God.' (Pentecost)