Sunan Ibn Majah, Book 1, Hadith 253 (In-Book)

It was narrated that Abu Umamah said: "The Prophet walked on a very hot day towards Baqi' Al-Gharqad (graveyard of Al-Madinah), and the people were walking behind him. When he heard the sound of their shoes, it affected his soul so he sat down until he made them go ahead of him, lest that make him feel too proud."

حَدَّثَنَا مُحَمَّدُ بْنُ يَحْيَى، حَدَّثَنَا أَبُو الْمُغِيرَةِ، حَدَّثَنَا مُعَانُ بْنُ رِفَاعَةَ، حَدَّثَنِي عَلِيُّ بْنُ يَزِيدَ، قَالَ سَمِعْتُ الْقَاسِمَ بْنَ عَبْدِ الرَّحْمَنِ، يُحَدِّثُ عَنْ أَبِي أُمَامَةَ، قَالَ مَرَّ النَّبِيُّ ـ صلى الله عليه وسلم ـ فِي يَوْمٍ شَدِيدِ الْحَرِّ نَحْوَ بَقِيعِ الْغَرْقَدِ وَكَانَ النَّاسُ يَمْشُونَ خَلْفَهُ فَلَمَّا سَمِعَ صَوْتَ النِّعَالِ وَقَرَ ذَلِكَ فِي نَفْسِهِ فَجَلَسَ حَتَّى قَدَّمَهُمْ أَمَامَهُ لِئَلاَّ يَقَعَ فِي نَفْسِهِ شَىْءٌ مِنَ الْكِبْرِ ‏.‏

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