John 6:19 WEB

¹⁷  and they entered into the boat, and were going over the sea to Capernaum. It was now dark, and Jesus had not come to them.

¹⁸  The sea was tossed by a great wind blowing.

¹⁹  When therefore they had rowed about twenty-five or thirty stadia,{25 to 30 stadia is about 5 to 6 kilometers or about 3 to 4 miles} they saw Jesus walking on the sea, and drawing near to the boat; and they were afraid.

²⁰  But he said to them, 'I AM. Don't be afraid.'

²¹  They were willing therefore to receive him into the boat. Immediately the boat was at the land where they were going.