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 great passages of the Fourth Gospel, and indeed of the New Testament. In it there are two great lines of thought that we must try to analyse. 