Disciples commanded to wash each other's feet
John 13:14–16 (ASV)
14If I then, the Lord and the Teacher, have washed your feet, ye also ought to wash one another’s feet. 15For I have given you an example, that ye also should do as I have done to you. 16Verily, verily, I say unto you, a servant is not greater than his lord; neither one that is sent greater than he that sent him.