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.

 This is one of the most wonderful stories in the Fourth Gospel, and it is all the more wonderful when we press behind the meaning of the Greek to find that it really describes not some extraordinary miracle, but a simple incident in which John found, in a way he never forgot, what Jesus was like. 