Mbh 12.191.6a

"'"Bhrigu said, 'In days of yore, the divine Brahman, for benefiting the world, and for the protection of righteousness, indicated four modes of life.[573] Amongst them, residence in the abode of the preceptor is mentioned as the first (in order of time). He who is in this mode of life should have his soul cleansed by purity of conduct, by Vedic rites, and by restraints and vows and humility. He should worship the morning and evening twilights, the Sun, his own sacred fire, and the deities. He should cast off procrastination and idleness. He should cleanse his soul by saluting his preceptor, by studying the Vedas, and by listening to his preceptor's instructions. He should perform his ablutions thrice (viz., in the morning, noon, and evening). He should lead a life of celibacy; attend to his sacred fire; dutifully serve his preceptor; daily go out on a round of mendicancy (for supporting himself); and give ungrudgingly unto his preceptor the whole of what is obtained in alms. Willingly accomplishing everything that the commands of his preceptor may indicate, he should be ready to receive such Vedic instruction as his preceptor may give him as a favour.[574] On this subject there is a verse: That Brahmana who obtains his Veda by attending with reverence upon his preceptor, succeeds in attaining to heaven and obtains the fruition of all his desires. The domestic mode of life is called the second (in point of time). We shall explain to you all the pious acts and indications of that mode. Those who having completed their residence in the preceptor's abode return home, who are of pious conduct, who desire the fruits of a virtuous course of behaviour with spouses in their company, have this mode of life ordained for them. In it Virtue, Wealth, and Pleasure, may all be obtained. It is (thus) suited to the cultivation of the triple aggregate.