Concise Quran Commentary
It has been decreed for you that if one of you is about to die, and they are leaving a large amount of wealth behind, then they should make a will for their parents and close relatives, according to the sacred laws, not exceeding one third of the wealth (the rest of the wealth being distributed according to the laws of inheritance). Making this will is a firm duty on those who are mindful of Allah. This ruling was revealed before the verses about inheritance. When the verses about inheritance were revealed it was made clear who should inherit from the person who has died and how much they should inherit.