Laylat al-Bara'ah

Laylat al-Bara'ah (Shab-Barat)

Eve of the 15th day of the Islamic month of Shaban

This holy day is known as Laylat al-Bara'ah ("Night of Forgiveness") in Arabic and Shab-Barat in Persian. Followers observe the date by holding a vigil throughout the night. They congregate at the local mosque to pray, read the Qur'an, and set off fireworks. Like other Islamic traditions, the festival reflects the common elements as well as the differences between the religion's Shi'ite and Sunni sects.
Sunnis regard the holiday exclusively as a night in which one's fate for the upcoming year is determined. According to Sunni lore, every individual's destiny is recorded on a corresponding leaf on the Tree of Life. When Allah shakes this tree on the 15th of Shaban, he fixes the next year's course of events.
Simultaneous to observing these destiny traditions of Laylat al-Bara'ah, Shi'ites also celebrate the Birthday of the Twelfth Imam, a figure of paramount importance in the Shi'ite faith who is expected to redeem the world upon his second coming.

SOURCES:
AnnivHol-2000, p. 234
RelHolCal-2004, p. 147
UndIslam-2004, p. 291