Is a bequest for committing a sin or an unlawful act valid?
General Chapter
Al-Mughni
Book of Bequests
Primary text
A bequest commanding a sin or an unlawful act is invalid, regardless of whether the testator (Mūṣī) is a Muslim or a non-Muslim subject (Dhimmi). Therefore, a bequest to build or maintain a church or a fire temple, or to spend on them, is void. This view is held by Al-Shafi'i and Abu Thawr. The reasoning is that since the act itself is a disobedience (Ma'siyah), the bequest pertaining to it cannot be valid, similar to a bequest for immoral purposes.
Supporting text
The People of Opinion (Ashab al-Ra'y) hold that such a bequest is valid. Abu Hanifa permitted a bequest of one's land to be built into a church, though his two companions disagreed. The People of Opinion also permitted bequeathing funds to purchase wine or pigs and then giving them as charity to the non-Muslim subjects (Ahl al-Dhimmah), which is deemed invalid because it involves aiding in sin.