Vassa (Thai พรรษา, pansa or phansaa), also called Rains Retreat, is an intensive meditation retreat during the rainy season lasting for three lunar months from July to October. During this time Buddhist monks remain in a single place, generally in their temples. It is followed by two of the major festivals of the year among Theravada Buddhists, including Wan Awk Pansa. The retreat has largely been given up by Mahayana Buddhists.

The origins of the vassa tradition are ascribed to early Buddhist times. Gautama Buddha ordered his disciples to observe a pre-existing practice whereby holy men avoided travelling for a three month period during the rainy season, in order to avoid damaging crops.

The period begins on the first day of the waning moon in the eighth lunar month; the preceding day is Asanha Puja. The focus of celebration by the laity is the first day of vassa, Wan Kao Pansa, during which worshippers donate candles and other necessities to temples, a ceremony which has reached its most extravagant form in the Ubon Ratchathani Candle Festival.

It is an accepted practice in countries such as Thailand for the laity to take monastic vows for the vassa period and then to return to lay life. Commonly, the number of years a monk has spent in monastic life is expressed by counting up the number of vassas he has observed.

The end of vassa is marked by joyous celebration. The following month, the kathina ceremony is held, during which the laity gathers to make formal offerings of robe cloth and other requisites to the Sangha.

See also

• uposatha day