How do the scriptures describe an ideal Sanyasi?
Vishnu Purana, Book 3, Chapter 9 describes about the four orders of life: Brahmacharya, Grihastha, Vanaprastha and Sanyasa. In Vanaprastha, one prepare himself for Sanyasa, so I am mentioning all the properties of these two Ashramas.
Description of Vanaprastha Ashrama
When the householder, after performing the acts incumbent on his condition, arrives at the decline of life, let him consign his wife to the care of his sons, and go himself to the forests. Let him there subsist upon leaves, roots, and fruit; and suffer his hair and beard to grow, and braid the former upon his brows; and sleep upon the ground: his dress must be made of skin or of Káśa or Kuśa grasses; and he must bathe thrice a day; and he must offer oblations to the gods and to fire, and treat all that come to him with hospitality: he must beg alms, and present food to all creatures: he must anoint himself with such unguents as the woods afford; and in his devotional exercises he must be endurant of heat and cold. The sage who diligently follows these rules, and leads the life of the hermit (or Vánaprastha), consumes, like fire, all imperfections, and conquers for himself the mansions of eternity.
Description of Sanyasa Ashrama
Let the unimpassioned man, relinquishing all affection for wife, children, and possessions, enter the fourth order. Let him forego the three objects of human existence (pleasure, wealth, and virtue), whether secular or religious, and, indifferent to friends, be the friend of all living beings. Let him, occupied with devotion, abstain from wrong, in act, word, or thought, to all creatures, human or brute; and equally avoid attachment to any. Let him reside but for one night in a village, and not more than five nights at a time in a city; and let him so abide, that good-will, and not animosity, may be engendered. Let him, for the support of existence, apply for alms at the houses of the three first castes, at the time when the fires have been extinguished, and people have eaten. Let the wandering mendicant call nothing his own, and suppress desire, anger, covetousness, pride, and folly. The sage who gives no cause for alarm to living beings need never apprehend any danger from them. Having deposited the sacrificial fire in his own person, the Brahman feeds the vital flame, with the butter that is collected as alms, through the altar of his mouth; and by means of his spiritual fire he proceeds to his own proper abode. But the twice-born man, who seeks for liberation, and is pure of heart, and whose mind is perfected by self-investigation, secures the sphere of Brahmá, which is tranquil, and is as a bright flame that emits not smoke.
Srimada Bhagavata also describes the characteristics of Sanyasi.
SB 7.13.2 — A person in the renounced order of life may try to avoid even a dress to cover himself. If he wears anything at all, it should be only a loincloth, and when there is no necessity, a sannyāsī should not even accept a daṇḍa. A sannyāsī should avoid carrying anything but a daṇḍa and kamaṇḍalu.
SB 7.13.3 — The sannyāsī, completely satisfied in the self, should live on alms begged from door to door. Not being dependent on any person or any place, he should always be a friendly well-wisher to all living beings and be a peaceful, unalloyed devotee of Nārāyaṇa. In this way he should move from one place to another.
SB 7.13.4 — The sannyāsī should always try to see the Supreme pervading everything and see everything, including this universe, resting on the Supreme.
SB 7.13.5 — During unconsciousness and consciousness, and between the two, he should try to understand the self and be fully situated in the self. In this way, he should realize that the conditional and liberated stages of life are only illusory and not actually factual. With such a higher understanding, he should see only the Absolute Truth pervading everything.
SB 7.13.6 — Since the material body is sure to be vanquished and the duration of one’s life is not fixed, neither death nor life is to be praised. Rather, one should observe the eternal time factor, in which the living entity manifests himself and disappears.
SB 7.13.7 — Literature that is a useless waste of time — in other words, literature without spiritual benefit — should be rejected. One should not become a professional teacher as a means of earning one’s livelihood, nor should one indulge in arguments and counterarguments. Nor should one take shelter of any cause or faction.
SB 7.13.8 — A sannyāsī must not present allurements of material benefits to gather many disciples, nor should he unnecessarily read many books or give discourses as a means of livelihood. He must never attempt to increase material opulences unnecessarily.
SB 7.13.9 — A peaceful, equipoised person who is factually advanced in spiritual consciousness does not need to accept the symbols of a sannyāsī, such as the tridaṇḍa and kamaṇḍalu. According to necessity, he may sometimes accept those symbols and sometimes reject them.
SB 7.13.10 — Although a saintly person may not expose himself to the vision of human society, by his behavior his purpose is disclosed. To human society he should present himself like a restless child, and although he is the greatest thoughtful orator, he should present himself like a dumb man.
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