Non-Muslim without heirs leaving entire estate to Muslim friend
9-11-2017 | IslamWeb
Question:
Assalaamu alaykum wa rahmatullaahi wa barakaatuhu. I had a friend who was a non-Muslim and who passed away. She left behind a will which named me the sole beneficiary to their property and money. They had no living relatives or children. I would like to know if I am permitted to accept it.
Answer:
All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad 
is His slave and Messenger.
The will of a non-Muslim for a Muslim is valid, and it should be within one third of the estate, as we clarified in Fatwa 152317.
The Fiqh Encyclopedia reads, “The will of a non-Muslim is valid within the same limits wherein the will of a Muslim is valid.”
Therefore, if your non-Muslim friend made a will that you take something of her property, then you may take it. But if she made a will stating that you take her entire property because she does not have any heirs, then the scholars of Fiqh differed in opinion about the validity of the will of the one who had made a will of his entire wealth because he has no heirs.
Ibn Qudaamah 
said:
“With regard to the one who makes a will of his entire wealth while he has no 'Asabah (agnate relatives) nor a Mawla (a master who freed him when he was a slave), then it is permissible. It was also narrated that Imam Ahmad said in another narration, ‘It is not permissible except within one third. There are different narrations from Ahmad about the one who did not leave any relatives on the father's side nor has any heir entitled to a specific share. It was reported from Ahmad that his will is valid with his entire wealth; this is proven from Ibn Mas‘ood, and it was stated by ‘Ubaydah Al-Salmaani, Masrooq, Is-haaq, and the scholars of Iraq.’ Another narration reads, ‘It is only permissible within one third,’ and this is also the view of Maalik, Al-Awzaa'i, Ibn Shubrumah, Ash-Shaafi‘i and Al-‘Anbari. This is because he has 'Aaqilah (i.e. relatives who would pay blood money on his behalf, if needed, in case of the unintentional act of killing), so his will is not valid in more than one third, as in the case when he leaves an heir. In our view, the prevention of making a will with more than one third was due to the right of the heirs, as evidenced by the saying of the Prophet who said, ‘It is better for you to leave your heirs wealthy than to leave them poor, begging people.’ [Al-Bukhaari and Muslim] But in this case, he does not have any heir who has a right in his inheritance…”
This is the view favored by Ibn Al-Qayyim as he said:
“If a sick person who does not have any heir wants to make a will of his entire wealth to be spent in charity, is he entitled to do that? There are two views in this regard: the most correct one is that he is entitled to do that, because he was prevented by the Shariah to give more than one third when he has heirs to inherit from him. So the one who does not have any heir, then there is no objection to what he does with his wealth. If he fears that the ruler would invalidate his will and would not approve it because he does not follow the view that it is allowed, then in this case he may make a legal device by testifying that he owes a trustworthy person whom he trusts regarding his religion and honesty a debt that encompasses his entire wealth, and then he would ask that person to spend that wealth in certain channels once he gets hold of it (after his death).”
Allah knows best.