"After Jesus had washed their feet, he put his outer garment back on and returned to his place at the table. “Do you understand what I have just done to you?” he asked.

“You call me Teacher and Lord, and it is right that you do so, because that is what I am. I, your Lord and Teacher, have just washed your feet. You, then, should wash one another's feet. I have set an example for you, so that you will do just what I have done for you.

I am telling you the truth: slaves are never greater than their master, and messengers are never greater than the one who sent them. Now that you know this truth, how happy you will be if you put it into practice!”"

(John 13.12-17 GNB)

"Wash one another's feet." Ooh, that is a hard one. Do I really have to do it?

Which of the Ten Commandments does that fall under? None that I can think of. And it does not sound like "love others" either. I think this is more like the Beatitudes.

It comes with a promise: "how happy you will be if you put it into practice".

Promise notwithstanding, Jesus said "I have set an example for you, so that you will do just what I have done for you."