Srimad Bhagvata Mahapurana: Book 7: Chapter 12: Verses 1-15
An inquiry into right conduct (continued)
Narada began again : Dwelling in the house of his teacher, humble as a servant, with his senses (fully) controlled, and doing him good offices and bearing the strongest affection for him, a Brahmacari (a celibate student) should worship in the evenings and mornings his teacher, the sacred fire, the sun-god and Lord Visnu (the Chief of the gods) as well as (the deities presiding over) both the twilights (and noontide), silently muttering the holy Gayatri-Mantra with a concentrated mind. Well-regulated (in life), he should learn (take his lessons in) the Vedas from his teacher if (and when) called (by him) and should (invariably) bow (to him), touching the latter's feet with his head at the beginning as well as at the end
(of his lessons). Carrying (blades of) the (sacred) Kusa grass in his hands, he should wear a gridle (of a species of rush known by the name of Munja), deerskin and (two pieces of) cloth, the sacred thread and unkempt hair, and should (also) carry a staff and a Kamandalu (a water-pot generally made of cocoanut-shell) as enjoined by the scriptures. (Every) evening and morning he should go about begging for food and offer it to the teacher. He should partake of it, (only) if allowed; if not permitted on any day (e.g., on the Ekadasi day, when everybody is expected to observe a fast or live only on fruits etc., or on any other day by way of penalty for some transgression or even as a test as to what effect it is likely to have on his mind), he should fast. Possessing a good moral character, moderate in (his) diet, active, reverent and exercising control over his senses, he should deal with women as well as with those enslaved by women only as much as it is (absolutely) necessary. Anyone other than a householder, who has undertaken the great vow of continence, should shun (all) talk of women; (for) the senses, which are very turbulent (by nature), forcibly carry away (with them) the mind (even of one who is fully controlled). An adult student should never have (such personal service as) the combing of his hair, massaging and washing his body and inunction etc., done by the young wives of his teachers (even if they offer their services out of pure motherly love, treating him as their own son). It is a truism indeed that a young woman is (like) fire and a man is (akin to) a jar full of ghee (clarified butter). One should avoid (the presence of) even one's daughter when (she is) all by herself; (nay,) at other times (too) one should remain with her (only) so long as it is (absolutely) necessary. Until one has mastered his self, having (clearly) apprehended through self-realization that (all) this (the body, the senses and so on) is (only) illusory, the sense of duality (the feeling that woman is an object of enjoyment and I am the enjoyer) does not cease. (And) from that (sense of duality) indeed follows the perversity of the embodied soul (through identification with the body and other material things).
All this (whatever has been stated in verse 6 above) has been enjoined upon a householder (too), (nay,) even on a recluse (much more on an anchorite). Service to one's preceptor (also) is optionally laid down in the case of a householder, who is (ordinarily) expected to approach his wedded wife during the period favourable for procreation (sixteen days after menstruation). Those who have undertaken a vow of continence should give up (the use of) collyrium, inunction, massaging the body, (fellowship with) women, drawing, meat, spirituous liquor (in the case of those who are ordinarily allowed to drink it or honey in the case of others), garlands, perfumes, unguents and ornaments. Having thus lived in a teacher's house and studied and grasped the import of (all) the three Vedas (Rgveda, 'Yajurveda and Samaveda) along with the (six) sciences auxiliary to them and the Upanisads (philosophical treatises forming part, nay, the quintessence of the Vedas) according to his eligibility and capacity, and having made available to the teacher, if capable of doing so, the object of his desire, and (duly) permitted by him, he should enter (according to his predilections and fitness) the life of a householder (marry and beget children) or retire to the woods (take to the life of an anchorite) or renounce the world and wander forth as an ascetic mendicant (recluse) or continue there (in the teacher's house as a lifelong celibate). He should visualize Lord Visnu (who is above sense-perception) as having entered (taken up His abode in) the sacred fire, the teacher, his own self as well as all the (five) elements (viz., earth, water, fire, air and ether)-including the (diverse orders of) living beings dwelling in them-as their Inner Controller, even though He has not (really) entered them (having been already present in them by virtue of His pervading all as their very Cause).