Hadith 248:13
Hassan ibn Musa narrated to us, he said: Ibn Lahi'ah narrated to us, he said: Musa ibn Jubayr narrated to us, from Abu Umamah ibn Sahl ibn Hunayf, from his father, from the Prophet, may Allah bless him and grant him peace, that he said: "Whoever has a believer humiliated in his presence and does not aid him, while he is capable of aiding him, Allah the Exalted and Majestic will humiliate him before the heads of all creation on the Day of Resurrection."
حدثنا حسن بن موسى، قال: حدثنا ابن لهيعة، قال: حدثنا موسى بن جبير، عن أبي أمامة بن سهل بن حنيف، عن أبيه، عن النبي صلى الله عليه وسلم أنه قال: " من أذل عنده مؤمن فلم ينصره، وهو يقدر على أن ينصره أذله الله عز وجل على رءوس الخلائق يوم القيامة "