عَنْ أَبِي هُرَيْرَةَ رضي الله عنه عَنِ النَّبِيِّ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ قَالَ: «أَمَا يَخْشَى أَحَدُكُمْ - أَوْ: لاَ يَخْشَى أَحَدُكُمْ - إِذَا رَفَعَ رَأْسَهُ قَبْلَ الإِمَامِ، أَنْ يَجْعَلَ اللَّهُ رَأْسَهُ رَأْسَ حِمَارٍ، أَوْ يَجْعَلَ اللَّهُ صُورَتَهُ صُورَةَ حِمَارٍ».
The Prophet (may Allah's peace and blessings be upon him) clarifies the serious threat to the one who raises his head in prayer before his Imam, as Allah may transform his head into that of a donkey or transform his shape into that of a donkey.
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