From J

A. 12 So after he had washed their feet, and had taken his garments, and was set down again, he said unto them, Know ye what I have done to you?  

B. 13 Ye call me Master and Lord:  and ye say well; for so I am.

B’. 14  If I then,  your Lord and Master,

A’. have washed your feet; ye also ought to wash one another’s feet. 15 For I have given you an example, that ye should do as I have done to you.