What is a Waqf?
Waqf is a financial charitable institution established by withholding one's property to eternally spend its revenue on fulfilling certain needs depending on the choice and conditions made by the 'waqef' or the person who owns the property.
Simply a Waqf is where assets such as money or business holding or real estate are put aside for the benefit of the others and the future.
History of Waqf in Islam
The first religious waqf is the mosque of Quba' in Madinah, which was built upon the arrival of the Prophet Muhammad صلى الله عليه و سلم in 622. It stands now on the same lot with a new and enlarged structure. Six months later, Quba' was followed by the mosque of the Prophet صلى الله عليه و سلم in the center of Madinah. Mosques and real estates confined for providing revenues to spend on mosques' maintenance and running expenses are in the category of religious waqf.
One of the Prophet Mohamed's saying that encourages 'sadaqa jariya', the waqf included, is "If the son of Adam dies, his work stops except for three; a sadaqa jariya, a useful science, and a good son who prays for him".
The religious origin of waqf in Islam started with a story of the second caliph Omar Ibn el Khattab when he was granted gardens after opening Khaiber and came to the prophet asking him about the best way to make the poor benefit from this land. The prophet Muhammad صلى الله عليه و سلم advised him to eternally withhold the land and spend its revenue on the poor without being subject to be sent, nor donated nor inherited to anybody. Since this incident, waqf has been spread among Muslims at the time of the prophet and continued after him for long centuries.