Based on John 13:4-12
Jesus and his disciples had gathered for a meal as part of the Passover celebration. The disciples did not understand that this would be their last supper together. Suddenly, while they were eating, Jesus rose from the table, took off his robe and wrapped a towel around his waist. He poured water into a bowl and began to wash the disciples' feet.
When He reached Simon Peter, Peter stopped Him. "Lord, you want to wash my feet?" Jesus replied, "I know you don't know what I am doing now; but later you will understand." Peter resisted. "No, you will never wash my feet." "If I do not wash your feet," Jesus replied, “you are not one of mine." "Lord,” Peter responded, “after you wash my feet, wash my hands and my head also!"
After Jesus finished washing the feet of all of the disciples, He put on his robe and returned to the table. He then said to them all, “If you call me your Lord and Teacher and I have washed your feet, you should also wash each other's feet. I have given you this example so you should do as I have done.”
"Ye call me Master and Lord: and ye say well; for so I am. If I then, your Lord and Master, have washed your feet; ye also ought to wash one another's feet. For I have given you an example, that ye should DO AS I HAVE DONE to you.” John 13:15 (KJV)