Reference for Bava Metzia 168:18
חלש דעתיה דרבי אתא א"ל לאבוה אמר ליה בני אל ירע לך שהוא ארי בן ארי ואתה ארי בן שועל
and they brought up his bier, and carried it to his father's vault, which they found encircled by a serpent. Said they to it, 'O snake, O snake, open thy mouth, and let the son enter to his father.' Thereupon it opened [its mouth] for them. Then Rabbi sent [messengers] to propose [marriage] to his wife. She sent back: 'Shall a utensil, in which holy food has been used, be used for profane purposes!' There [sc. in Palestine] the proverb runs: Where the master hung up his weapons, there the shepherd hung up his wallet. He sent back word, 'Granted that he outstripped me in learning, was he [also] my superior in good deeds?' She returned, 'Yet at least he outstripped you in learning, though I did not know it. But I do know [that he exceeded you] in [virtuous] practice, since he submitted himself to mortification.'