Thirty Minor Upanishads
Chapters
Thirty Minor Upanishads: 21. Naraḍaparivrājaka...

alms-food who preserves the same countenance when he is beaten, as when he is worshipped or prostrated to. He becomes fit to be the eater of alms-food who is of the firm certitude that he is no other than the non-dual and indestructible Brahman, otherwise named Vāsuḍeva. He in whom are existent śānṭi (control of the organs), śama (control of mind), purity (of mind and body), saṭya (truth), sanṭosha (contentment), ārjava (straightforwardness), poverty, and non-ostentatiousness should be in the order of life of kaivalya (sannyāsa). When one does not, through actions, mind, or speech, commit any sinful action to any being, then he becomes fit for eating alms-food. Having become quiescent (through the control of the mind), having practised the ten kinds of ḍharmas, having, according to rules, studied veḍānṭa, and having paid the three debts (to ḍevas, ṛshis, and piṭṛs), one should take up sannyāsa. Courage, fortitude, the control of the body, honesty, purity of (mind and body), control of the (inner) organs, shame, knowledge, truth, and absence of anger—these ten are the characteristics of ḍharma. One who does not look back (with pleasure) upon past enjoyments, nor forward into the future, and one who does not rejoice in the present, is fit to become a sannyāsin. One who is able to control within, the inner organs and without, the external organs, may be in the order of life of kaivalya. One who while in life is not affected by pleasures and pains, as the body is unaffected by them after death, may be in the order of life of kaivalya.

"An ascetic of the Paramahamsa (order) shall wear two loin-cloths, one ragged cloth, and one staff. Nothing more is ordained (in his case). Should he through desire wear more than these, he will fall into the hell of raurava and be born into the womb of an animal. Having stitched together old and clean cloths into one and having coloured it with red (ochre), he should wear it as his upper cloth. He may be with one cloth or even without it. He should roam about alone with the sole vision (of Brahman), devoid of desires; but he may be in one place alone in the rainy season. Having quite abandoned his family, including son and wife, veḍānṭa, sacrifice, and the sacred thread, the ascetic should wander incognito.