In «أَطْعَمَهُمْ مِنْ», the first word ends in mīm sākinah and the next begins with a vowelled mīm. It produces idghām shafawī with ghunnah.
The same pattern appears again in «آمَنَهُمْ مِنْ» later in the verse. Contrast «تَرْمِيهِمْ بِحِجَارَةٍ», where the following bāʾ triggers ikh-fāʾ shafawī. It is not the mere presence of mīm but the next letter that determines the rule.
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Aṭʿamahum min: mīm assimilates into mīm
Al-Fīl and Quraysh: Applied Iẓhār, Ikhfāʾ, Idghām, Madd and Waqf
In «أَطْعَمَهُمْ مِنْ», the first word ends in mīm sākinah and the next begins with a vowelled mīm. It produces idghām shafawī with ghunnah.
The same pattern appears again in «آمَنَهُمْ مِنْ» later in the verse. Contrast «تَرْمِيهِمْ بِحِجَارَةٍ», where the following bāʾ triggers ikh-fāʾ shafawī. It is not the mere presence of mīm but the next letter that determines the rule.