The familiar forms مَا and مَنْ can also connect a statement to what or whom it describes. In this use, they are not asking a question.
Form
Relative sense
Example
مَا
what / whatever
لِلَّهِ مَا فِي السَّمَاوَاتِ وَالْأَرْضِ
مَنْ
who / whoever
فَذَكِّرْ بِالْقُرْآنِ مَنْ يَخَافُ وَعِيدِ
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Relative Nouns and Their Completing Clauses
The familiar forms مَا and مَنْ can also connect a statement to what or whom it describes. In this use, they are not asking a question.
Form
Relative sense
Example
مَا
what / whatever
لِلَّهِ مَا فِي السَّمَاوَاتِ وَالْأَرْضِ
مَنْ
who / whoever
فَذَكِّرْ بِالْقُرْآنِ مَنْ يَخَافُ وَعِيدِ