The last of the three Refuges is the Sangha. In its primary sense this means the Arya-Sangha, or Assembly of the Elect, consisting of all those who have succeeded in traversing at least that stage of the Path whence retrogression into the Round for more than seven karma-resultant births is impossible. Such are the Stream-Entrants, the Once-Returners, the Non-Returners, the Arhants, and the Bodhisattvas.
Even as the Buddha is symbolized by the sacred icon and the Dharma by the handwritten or printed volumes of the Scriptures, so the Arya Sangha is represented, for practical purposes, by the Bhikshu-Sangha or Order of Monks. This great institution, which with the possible exception of its Jain counterpart is the oldest surviving religious order in the world, came into existence within a few months of the Buddha’s Enlightenment.
It consisted-and ideally still consists-of those of the Buddha’s followers who, having renounced the household life, devote the whole of their time and all their energies to the realization of Nirvana. Like the Dharma, the Sangha passed through various stages of development.
At first, during the early lifetime of the Founder, the Sakyaputra sramanas, as they were called, remained outwardly indistinguishable from the other religious fraternities of the time. What in fact set them apart was the special Dharma they professed. They, too, were of eleemosynary and eremitical habit, assembled twice a month on the days of the full moon and new moon, were of fixed residence during the rains, and so on.
The second period of development may have started before the Parinirvana. It saw the compilation of a Rule of 150 articles known as the Pratimoksha, the recitation of which replaced the original chanting of Dharma- stanzas at the fortnightly assemblies.
Finally, the Sangha became coenobitical, whereupon the primitive undivided ‘Bhikshu-Sangha of the Four Quarters’ split up into a number of virtually autonomous local communities, and the Pratimoksha had to be supplemented by the Skandhakas or complete institutes of coenobitical monasticism.
All these developments occurred within the space of about two centuries. Pratimoksha and Skandhakas together constitute the Vinaya, a term originally connoting simply the practical or disciplinary aspect of the Dharma.
Parallel with the Bhikshu-Sangha there developed the Bhikshuni-Sangha or Order of Nuns. But according to the tradition the Buddha was reluctant to allow women to go forth into the homeless life and, in the history of Indian Buddhism at least, the Bhikshuni-Sangha plays an insignificant part.
In a more general sense the Sangha comprises the entire Buddhist community, sanctified and unsanctified, the professed religious and the lay devotees, men and women. As such it is sometimes known as the Mahasangha or ‘Great Assembly’. Lay devotees (upasakas and upasikas) are those who go for refuge to the Three Jewels, worship the relics of the Buddha, observe the Five Precepts of ethical behaviour, and support the monks.
The growth of coenobitical monasticism naturally encouraged the development within the Sangha of different regional traditions which, after being consolidated into distinct versions of the Dharma, eventually emerged as independent sects.
Thus a century or more after the Parinirvana tensions arose between the monks of the east and the monks of the west; and the Mahasanghikas, who were more sympathetic to the spiritual needs of the laity, seceded from the Sthaviravadins (more commonly known as Theravadas, the Pali form of the name) who tended to interpret the Dharma in exclusively monastic terms.
This was the first formal schism within the Sangha. During the century that followed the Sthaviravadins subdivided twice. First came the schism of the Pudgalavadins, who believed in the existence of the person as a real absolute fact; then that of the Sarvastivadins, who asserted the real existence of the ultimate elements of experience (dharma) throughout the three periods of time.
In this way there had arisen, by the time of Asoka, four independent monastic corporations, each with its own centres, its own ordination-lineage, and its own orally transmitted version of the Dharma, its own distinctive tenets, and its own peculiarities of outward observance. Together with their respective sub-divisions, the four make up the so-called ‘Eighteen Sects’ (actually there were many more) of early Buddhism.
In contradistinction to the Mahayana, ‘The Great Vehicle’, the seeds of which were transmitted by the Mahasanghikas and their offshoots, all the other sects, but especially the Sarvastivadins, were retrospectively designated the Hinayana, ‘The Inferior Vehicle’.