They are denouncing him for applying the Sunnah and saying that it divides the Muslims

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The rights of one Muslim over another include those that are obligatory and those that are mustahabb
Meaning of the verse “And were it not that all mankind would have become of one community…” [az-Zukhruf 43:33]

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He promised his mother to give her money that she could put towards building a mosque, then she died
If a brother usurped his brother’s rights, there is nothing wrong with referring the matter to the qaadi (judge), even if that upsets the mother
Trust (amaanah) in Islam
The rights of one Muslim over another include those that are obligatory and those that are mustahabb
Meaning of the verse “And were it not that all mankind would have become of one community…” [az-Zukhruf 43:33]

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