The purpose of ascetic austerities (Sanskrit, tapas) before the Buddha was self-abnegation. This view was predicated on a dualism of flesh and spirit, or body and mind in contemporary terms. Ascetics (saddhus) mortified the body to release the spirit and to develop magical powers. The Buddha, who had practiced to the extreme for six years, ultimately found them NOT conducive to enlightenment.
It was not, in and of itself, even conducive to Samadhi (concentration manifesting as serene mastery of the Eight Jhanas). Many yogis followed gurus and their own train of thought on the matter: they tortured the body in the mistaken assumption that it was the cause of lust. Since the mind is the cause, with the body simply following suit, many ascetics ultimately failed to do more than simply suppress the spiritual defilements that obstruct insight.
With the suppression of defilements (e.g., nivarana, kilesa, asava to be specific), they developed psychic hearing, seeing, and otherwise sensing. These were called developing the "divine eye" and so on by the Buddha. But insight, and the karma-that-ends-karma, eluded them.
Nevertheless, for ordained individuals who chose, the Buddha did recommend thirteen practices. These were "sane ascetic practices." They are never practiced all at once, nor are they even all practiced. Instead, they are chosen and practiced for a limited time with the intention of overcoming some deleterious habit, tendency, or character trait.
THE SANE ASCETIC PRACTICES (dhutanga)
These are the thirteen kinds of ascetic practices have been allowed by the Budda to recluses who have given up the things of the flesh and, regardless of body and life, are desirous of undertaking a practice in conformity [with their aim].
- refuse-rag-wearer’s practice
- triple-robe-wearer’s practice
- alms-food-eater’s practice
- house-to-house-seeker’s practice
- one-sessioner’s practice
- bowl-food-eater’s practice
- later-food-refuser’s practice
- forest-dweller’s practice
- tree-root-dweller’s practice
- open-air-dweller’s practice
- charnel-ground-dweller’s practice
- any-bed-user’s practice
- sitter’s practice
For details on these practices read More >>
- They are also explained in the Buddhist Dictionary: Manual of Terms and Doctrines
- Sadhus: the Holy Men of India by Rajesh Bedi
- Sadhus: India's Mystic Holy Men by Dolf Hartsuiker
- Spanish blogspot site (excellent video clips) on practices