Bablyonian Talmud, Book 5: Tracts Aboth, Derech Eretz-Rabba, Eretz-Zuta, and Baba Kama (First Gate), tr. by Michael L. Rodkinson, , at sacred-texts.com
SEVEN things mark the clod, etc. (See Aboth, Chap. V., Mishna J.) A scholar must be careful in his eating, drinking, washing, anointing, in wearing the sandals, in his walking, dressing, in the use of his voice, in the act of spitting, and also with all his good deeds. As a bride, who so long as she is in her father's house pursues
privacy and modesty, and when she is given away in marriage announces publicly, saying: "All those who can come to testify against me, let them come and do so," so a scholar must pursue privacy in his deeds but publicity in his ways; namely, he must run after truth but not after falsehood, after honesty but not after robbery, after modesty but not after haughtiness, after peace but not after war, after the advice of the old but not after that of the young. He shall rather follow behind a lion than behind a woman.
Who respects the sages? he who gives food, drink, dress, shoes, goes out to meet and accompanies when leaving, without distinction between rabbi or disciple. And who shows them disrespect? he who occupies the seat of his master even during his absence, or substitutes him (without permission) in lecturing, or contradicts him.