Full Sharh — Mishkat al-Masabih 2053
وَعَنْ أَبِي هُرَيْرَةَ رَضِيَ اللَّهُ عَنْهُ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «مَنْ قَرَأَ (حم) الدُّخَانِ فِي لَيْلَةٍ أَصْبَحَ يَسْتَغْفِرُ لَهُ سَبْعُونَ أَلْفَ مَلَكٍ» . رَوَاهُ التِّرْمِذِيُّ وَقَالَ: هَذَا حَدِيث غَرِيب وَعمر بن أبي خَثْعَمٍ الرَّاوِي يُضَعَّفُ وَقَالَ مُحَمَّدٌ يَعْنِي الْبُخَارِيَّ هُوَ مُنكر الحَدِيث
English Translation
He reported God’s messenger as saying, “If someone recites Hā’ Mīm ad-Dukhān (Qur’ān, 44) any night, seventy thousand angels will ask forgiveness for him in the morning.” Tirmidhī transmitted it, saying that this is a gharīb tradition and that ‘Umar b. Abū Khath'am the transmitter is declared to be weak. Muhammad, i.e. Bukhārī, said his traditions were rejected.
Source
Mishkat al-Masabih(مشكاة المصابيح)
The Excellent Qualities of the Qur'an
Hadith Number
2053