Mispronouncing some words of Surah al-Fatiha

Question

If an imam recites “رابِّ العالمين” instead of “رَبِّ الْعَالَمِينَ”, “ياوم الدين” instead of “يَوْمِ الدِّينِ”, and “مُسْتَقَيم” instead of “مُسْتَقِيم”, will the prayer be valid in this case or not?

Answer

If these words were recited in such a way that the letter “ر” (ra’) in “رَبِّ الْعَالَمِينَ” was pronounced with tafkhim (heavily), so that the listener had the impression of an alif with it; the letter “و” (waw) in “يَوْمِ الدِّينِ” was recited as a soft letter (lin)

Source: Fatawa Mahmudiyya

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