The Ruling on a Bequest Made for the Purpose of Preventing the Sons From Inheriting

Question :

A man has eight sons, six of them obedient to Allah and two of them disobedient to Allah - they do not fast or pray and they are disrespectful to their parents. Because of this, he wrote in his will that they will not inherit anything which he left, unless they turn in repentance to Allah before he is taken from them (i.e., until he dies). I request advice regarding the correctness of this will."

Answer:

This will is not permissible, because it contradicts the requirements of the Islamic Law and justice which Allah commanded - especially between sons, according to the Hadith narrated by Ahmad and Abu Dawud may Allah have mercy on them on the authority of Abu Umamah, may Allah be pleased with him, in which the Messenger of Allah said:
"Verily Allah gave every deserving person his right, so there is no bequest for the heir."

And, the Hadith narrated by Al-Bukhari and Muslim may Allah have mercy on them on the authority of An-Nu'man bin Bashir, may Allah be pleased with him, in which it is stated that his father came to the Prophet ﷺ and said: "I have given a gift of a slave of mine to this, my son." The Prophet said:
"Have you given each son a gift like the one you gave to this one?"

He said: "No." He said:
"Then return it."

In the wording of Muslim, he added:
"Fear Allah and act with justice between your sons."

If it is confirmed with a legal confirmation that which necessitates a verdict of disbelief on them, such as abandoning prayer, at the time of the death of their father, then there is no inheritance for them, even if it was not so willed for them, according to the words of the Prophet :
"The Muslim does not inherit the disbeliever, neither does the disbeliever inherit the Muslim."

And may peace and blessings be upon our Prophet, Muhammad and upon his family and Companions.