The Mahabharata of Krishna-Dwaipayana Vyasa…
“ Becoming pure in body and mind, and acquiring cleverness and other virtues, he should now and then speak what is agreeable. Subduing his senses, he should look at his preceptor without eyes of longing curiosity. [996] He should never eat before his preceptor has eaten; never drink before his preceptor has drunk; never sit down before his preceptor has sat down; and never go to bed before his preceptor has gone to bed. He should gently touch his preceptor's feet with upturned palms, the right foot with the right and the left with the left. ”
