COMMENTARY on 4:12
Mustafa Khattab:

Translation:
You will inherit half of what your wives leave if they are childless. But if they have children, then ˹your share is˺ one-fourth of the estate—after the fulfilment of bequests and debts. And your wives will inherit one-fourth of what you leave if you are childless. But if you have children, then your wives will receive one-eighth of your estate—after the fulfilment of bequests and debts. And if a man or a woman leaves neither parents nor children but only a brother or a sister ˹from their mother’s side˺, they will each inherit one-sixth, but if they are more than one, they ˹all˺ will share one-third of the estate5—after the fulfilment of bequests and debts without harm ˹to the heirs˺.5 ˹This is˺ a commandment from Allah. And Allah is All-Knowing, Most Forbearing.
Commentary:
5   If there are two or more brothers and sisters from the mother’s side, they share one-third equally—the female will receive the same share of the male.

 

A. Yusuf Ali:

Translation:
In what your wives leave, your share is a half, if they leave no child; but if they leave a child, you get a fourth; after payment of legacies and debts. In what you leave, their share is a fourth, 519 if you leave no child; but if you leave a child, they get an eighth; after payment of legacies and debts. If the man or woman whose inheritance is in question, has left neither ascendants nor descendants, 520 but has left a brother 521 or a sister, each one of the two gets a sixth; but if more than two, they share in a third; after payment of legacies and debts; so that no loss 522 is caused (to any one). Thus is it ordained by Allah. and Allah is All-knowing, Most Forbearing.
Commentary:

519  The husband takes a half of his deceased wife's property if she leaves no child, the rest going to residuaries; if she leaves a child, the husband gets only a fourth. Following the rule that the female share is generally half the male share, the widow gets a fourth of her deceased husband's property, if he leaves no children, and an eighth if he leaves children. If there are more windows than one, their collective share is a fourth or an eighth as the case may be: inter se they divide equally.

520  The word in Arabic is kalalah, which is so construed usually. But it was nowhere defined authoritatively in the lifetime of the Messenger. This was one of the three terms about which Umar wished that the Messenger had defined than in his lifetime, the other two being khilafah, and riba (usury). On the accepted definition, we are concerned with the inheritance of a person who has left no descendant or ascendant (however distant), but only collaterals, with or without a widow or widower. If there is a widow or widower surviving, she or he takes the share as already defined, before the collaterals come in.

521  A "brother or sister" is here interpreted to mean a uterine brother or sister, i.e., a brother or sister by the same mother but not by the same father, as the case of full brothers and sisters or brothers and sisters by the same father but different mothers is understood to be dealt with later, in the last verse of this Surah. The uterine brother or sister, if only one survives, takes a sixth, if more than one survives, they take a third collectively, and divide among themselves; this on the supposition that there are no descendants or ascendants, however remote. There may, however, be a widow or widower surviving: she or he takes her or his share, as already specified. The shares of collaterals generally are calculated on a complicated system which cannot be described in a brief note. For these, and the rules about Residuaries (‘ Asaba) reference should be made to special legal treatises.

522  Debts (in which funeral expenses take first rank) and legacies are the first charge on the estate of a deceased person, before distribution takes place. But equity and fair dealing should be observed in all matters, so that no one's interests are prejudiced. Thus funeral expenses should be reasonable; debts must be genuine and not reckless debts; and the shares must be calculated with fairness.

 

Muhammad Asad:

Translation:
And you shall inherit one-half of what your wives leave behind, provided they have left no child; but if they have left a child, then you shall have one-quarter of what they leave behind, after [the deduction of] any bequest they may have made, or any debt [they may have incurred]. And your widows 9 shall have one-quarter of what you leave behind, provided you have left no child; but if you have left a child, then they shall have one-eighth of what you leave behind, after [the deduction of] any bequest you may have made, or any debt [you may have incurred]. And if a man or a woman has no heir in the direct line, but has a brother or a sister, then each of these two shall inherit one-sixth; but if there are more than two, 10 then they shall share in one-third [of the inheritance], after [the deduction of] any bequest that may have been made, or any debt [that may have been incurred], neither of which having been intended to harm [the heirs]. 11 [This is] an injunction from God: and God is all-knowing, forbearing.
Commentary:
9  Lit., "they".
10  Lit., "more than that". According to most of the classical commentators, this passage refers to half-brothers and half-sisters. The inheritance of full brothers and sisters is dealt with at the end of this surah (verse 176).
11  This refers to bequests and fictitious debts meant to deprive the heirs of their legal shares. According to several authentic Traditions, the Prophet forbade, in cases where there are legal heirs, the making of bequests to other persons in excess of one-third of one's estate (Bukhari and Muslim). If, however, there are no near of kin legally entitled to a share of the inheritance, the testator is free to bequeath his fortune in any way he desires.