http://www.accesstoinsight.org/ptf/dhamma/sila/uposatha.html
Uposatha days are times of
renewed dedication to Dhamma practice, observed by lay followers
and monastics throughout the world of Theravada Buddhism.
For monastics, these are often days of more intensive reflection
and meditation. In And how is the defiled mind cleansed through the
proper technique?many monasteries physical labor (construction
projects, repairs, etc.) is curtailed. On New Moon and Full Moon
days the fortnightly confession and recitation of the Bhikkhu
Patimokkha (monastic rules of conduct) takes place.
Lay people observe the Eight Precepts on Uposatha days, as a
support for meditation practice and as a way to re-energize
commitment to the Dhamma. Whenever possible, lay people use these
days as an opportunity to visit the local monastery, in order to
make special offerings to the Sangha, to listen to Dhamma, and to
practice meditation with Dhamma companions late into the night. For
those not closely affiliated with a local monastery, it can simply
be an opportunity to step up one's efforts in meditation, while
drawing on the invisible support of millions of other practicing
Buddhists around the world.
And the Buddha said:
http://www.accesstoinsight.org/tipitaka/an/an03/an03.070.than.html
"And what is the Uposatha of the
Noble Ones? It is the cleansing of the defiled mind through the
proper technique.
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