Began to wash ... - It was uniformly the office of a servant to wash the feet of guests, 1 Samuel 25:41. It became a matter of necessity where they traveled without shoes, and where they reclined on couches at meals. It should be remembered here that the disciples were not sitting at the table, as we do, but were lying with their feet extended from the table, so that Jesus could easily have access to them. See the notes at Matthew 23:6.
Related Commentaries of John 13:5
John 13:5
5 After that he poureth water into a bason, and began to wash the disciples' feet, and to wipe them with the towel wherewith he was girded.