At Islamic law, a bequest may not exceed one-third of the estate. This is sometimes termed ‘the discretionary third.’ This proportion may only be increased with the authorisation of the legal heirs who are entitled to the majority share (2/3rds) pursuant to the applicable Qur’anic provisions.

A bequest ‘may be real or movable property, monies, rights in rem, all of which are inheritable, or it may be a usufruct (whether for life or for a definite period), or anything that is capable of being transferred. The bequest need not be in existence at the time of making the will, but must exist at the time of the testator’s death. It must be capable of being inherited or transferred, owned by the testator and in existence at the time of his death, and it is limited to one third of the estate.  Like the inheritance estate, a bequest must be capable of being assessed, acquired and used, such as property, both movable and immovable, rights and usufructs, apart from the personal non-pecuniary rights and uses. No testator can create by will an estate repugnant to law[…]’

The property in a bequest ‘shall be in existence and owned by the testator. This condition applies to property as contradistinction from usufruct. A will shall be void if the bequest, being a defined property per se or part of a defined whole, is not existing at the time when the will is made, since no person has the right to dispose of property he does not own. Such a will shall remain void even if the testator subsequently becomes the owner of the subject of the bequest, unless a new will is then made. Nevertheless, if the subject of the bequest is part of the whole property or class of property, e.g. a quarter of one-third of the estate or of books or animals, the will shall be valid provided that such property exists at the time of the death of the testator. A bequest need not be in the actual acquisition of the testator at the time of his death, but may be in the hands of a third party, e.g. a trust with a lien or a debt with a debtor, or even in the possession of a usurper. That the bequest shall not exceed one-third of the estate is a condition for a valid will to take effect. A Muslim who leaves heirs cannot dispose by will of more than one-third of what remains of his estate after payment of funeral expenses and debts. The remaining two-thirds of the estate is distributed according to the inheritance law among his heirs. A bequest in a will in excess of the legal one-third may be validated by the consent of the heirs, expressly or by implication, after the death of the testator […] Where some and not all of the heirs consent to the bequest, it shall be payable to the beneficiary from the shares of the consenting heirs alone.’


Jamal J. Nasir, The Islamic Law of Personal Status, second edition (Graham and Trotman, 1990), 269-270

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