Is it permissible for a Muslim to inherit from his apostate father, especially since the apostate father inherited from the Muslim's grandfather, who was a Muslim, knowing that an apostate does not inherit from a Muslim?

The majority of jurists hold that a Muslim does not inherit from an apostate, based on the Prophet's (peace be upon him) saying: "A Muslim does not inherit from an unbeliever, nor does an unbeliever inherit from a Muslim." The apostate's wealth then goes to the public treasury (Bayt al-Mal).

However, some scholars, including Mu'adh ibn Jabal and Shaykh al-Islam Ibn Taymiyyah, held that an apostate is inherited by his Muslim heir. They interpreted the aforementioned Hadith as referring to a belligerent unbeliever, not an apostate, and considered this greater in benefit than the benefit of marrying their women.

If the apostate inherited from his Muslim father, he took what was not rightfully his. If the son is the heir of the grandfather, due to the absence of other sons, and the wealth in the apostate's possession belonged to the grandfather, then the son has the right to take it. If there are other sons of the grandfather, they take the wealth. All of this is based on the assumption that apostasy is established and the man remained upon it until his death.