John 13:12-15

So when He had washed their feet, and put on His garments, and sat down again, He said to them, “Do you know what I have done to you? You call Me Teacher and Lord. You speak accurately, for so I am. If I then, your Lord and Teacher, have washed your feet, you also ought to wash one another’s feet. For I have given you an example, that you should do as I have done to you.