Jami' at-Tirmidhi
Jami` at-Tirmidhi 213
حَدَّثَنَا مُحَمَّدُ بْنُ يَحْيَى النَّيْسَابُورِيُّ، حَدَّثَنَا عَبْدُ الرَّزَّاقِ، أَخْبَرَنَا مَعْمَرٌ، عَنِ الزُّهْرِيِّ، عَنْ أَنَسِ بْنِ مَالِكٍ، قَالَ فُرِضَتْ عَلَى النَّبِيِّ صلى الله عليه وسلم لَيْلَةَ أُسْرِيَ بِهِ الصَّلَوَاتُ خَمْسِينَ ثُمَّ نُقِصَتْ حَتَّى جُعِلَتْ خَمْسًا ثُمَّ نُودِيَ يَا مُحَمَّدُ إِنَّهُ لاَ يُبَدَّلُ الْقَوْلُ لَدَىَّ وَإِنَّ لَكَ بِهَذِهِ الْخَمْسِ خَمْسِينَ . قَالَ وَفِي الْبَابِ عَنْ عُبَادَةَ بْنِ الصَّامِتِ وَطَلْحَةَ بْنِ عُبَيْدِ اللَّهِ وَأَبِي ذَرٍّ وَأَبِي قَتَادَةَ وَمَالِكِ بْنِ صَعْصَعَةَ وَأَبِي سَعِيدٍ الْخُدْرِيِّ . قَالَ أَبُو عِيسَى حَدِيثُ أَنَسٍ حَدِيثٌ حَسَنٌ صَحِيحٌ .
Unreviewed translation. All hadiths in this collection are available in five languages. Titles and introductions may remain in Arabic.
Muhammad ibn Yahya al-Naysaburi narrated to us: Abd al-Razzaq narrated to us: Ma‘mar informed us, from al-Zuhri, from Anas ibn Malik, who said: On the night the Prophet was taken on the Night Journey, the prayers were prescribed for him as fifty. They were then reduced until they were made five. Then a call came: ‘O Muhammad, My decree is not changed with Me, and these five are [counted] for you as fifty.’
A report on this subject is also related from Ubadah ibn al-Samit, Talhah ibn Ubayd Allah, Abu Dharr, Abu Qatadah, Malik ibn Sasaa, and Abu Sa‘id al-Khudri. Abu Isa said: The hadith of Anas is hasan sahih.
Notes and open questions — unreviewed
The source states both the reduction to five and that the five carry the measure of fifty.