John 13:11-14

For He knew the one who was betraying Him; for this reason He said, “Not all of you are clean.” So when He had washed their feet, and taken His garments and reclined at the table again, He said to them, “Do you know what I have done to you? You call Me Teacher and Lord; and you are right, for so I am. If I then, the Lord and the Teacher, washed your feet, you also ought to wash one another’s feet.