The Asahna Bucha (also known as Asalha Puja or Dhamma Day) is a Theravada Buddhist festival which typically takes place in July, on the full moon of the eighth lunar month. It is one of Theravada Buddhism’s most important festivals, celebrating as it does the Buddha’s first sermon in which he set out to his five former associates the doctrine that had come to him following his enlightenment. This first pivotal sermon, often referred to as “setting into motion the wheel of dhamma,” is the teaching which is encapsulated for Buddhists in the four noble truths: there is suffering (dukkha); suffering is caused by craving (tanha); there is a state (nibbana) beyond suffering and craving; and finally, the way to nirvana is via the eightfold path. All the various schools and traditions of Buddhism revolve around the central doctrine of the four noble truths.
This first sermon is not only the first structured discourse given by the Buddha after his enlightenment, it also contains the essence of all his subsequent teaching. At the end of the talk, one of the five participants recounted his understanding of what had been said and asked to be received as a disciple, a request the Buddha granted, thus establishing the first order of monks.
The day marks the beginning of Vassa, the Buddhist lent period also known as the 'Rains Retreat'. Ceremonies are held in Buddhist temples across Thailand. Many Thai people return to their ancestral homes to donate offerings to temples and listen to sermons. In the evening they will often perform a ceremony called 'wian tian', where they walk clockwise around the main shrine of the temple carrying a candle, incense sticks and lotus flowers.
During the day, monks chant mantras and preach the first sermon of the Buddha.
In Saraburi, local monks parade through the town with their alms bowls which, instead of the usual offerings of food, people will instead put flowers into their bowls. The monks then return to the temples and offer the flowers in honour of the Buddha.
Asanha Bucha Day is traditionally a popular day for young Thai men to enter the monkhood.
The day following Asahna Bucha is known as Khao Phansa or 'Buddhist Lent'. It marks the beginning of the three-month ‘Phansa’ period, during which all monks should stay in their temples and not travel. During the lent period, elaborate wax candles are kept burning. In the city of Ubon a Candle Festival is held where the people parade through the streets by candlelight and the winners of best candle design are announced.
Buddhist Lent Day is also a public holiday in Thailand, though banks are not closed.