The term waqf (pl. awqaf) literally means "confinement and prohibition". For instance, to donate a house in waqf means you devote it and its profits for the cause of Allah (Alrazi's Mukhtar Alsihah, p.733). Most of the legal definitions put forward by scholars of Jurisprudence revolve around the detention of an asset and the devoting of its profit or products in charity" (Ahmad ibn Hanbal's Alkafi 448 /2). The rationale of the legality of Waqf in Islam is based on the Quran and Sunnah. Allah Almighty says,

“You will not attain piety until you spend of that which You love.” [Qur’an: Al-Imran, 92]

When the above verse was revealed, Abu Talha (may Allah be pleased with him) proceeded to the Prophet (peace and blessings of Allah be on him) and said, “O, Prophet of Allah! Of my property I love Birha the most which I want to give in charity for Allah's Sake, hoping for its reward from Allah as you please.

The Prophet (peace and blessings of Allah be on him) remarked: “Hurrah! Hurrah! Hurrah!  It is a profitable property (to Allah)! I have heard what you have said, and I recommend that you distribute it among your relatives." Then Abu Talha distributed that garden among his relatives and cousins. (See the story of endowing this property in Sahih Albukharu, the Book of Instructions, Chapter of “If one endowed an area of land without giving details, as well as Sahih Muslim, the Book of Zakat, Chapter of the virtue of spending on relatives).  Another hadith proving the legality of waqf reads, “When a man dies, only three deeds will survive him: continuing alms, profitable knowledge and a child praying for him” (Narrated by Muslim, the Book of the Will documenting, Chapter of what reward attained by the man after death). Alhafiz Alnawawi commented on this hadith saying, “the continuing alms means waqf (endowment) … it also shows how appropriate and rewarding waqf is” (Alnawawi’s Commentary on Sahih Muslim 11/88).

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