Yochanan 13:12-16

Therefore, when he washed their feet and resuited himself into his kaftan, Rebbe, Melech HaMoshiach reclined at tish again and said to them, Do you have da'as of what I have done for you? You call me Rabbeinu and Adoneinu, and you say well, for Ani Hu. If, therefore, I, being Rebbe and Adon, washed your feet, you ought to wash the feet of one another also. For I gave you a mofet that as I did to you, you may do also. Omein, omein, I say to you, an eved is not greater than his Adon, nor is a shliach (one sent) greater than his Meshalle'ach (Sender).