Jami at-Tirmidhi 796
Jami at-Tirmidhi · Book 8: The Book on Fasting · Something Else About That
Aishah narrated:
حَدَّثَنَا قُتَيْبَةُ ، حَدَّثَنَا عَبْدُ الْوَاحِدِ بْنُ زِيَادٍ ، عَنِ الْحَسَنِ بْنِ عُبَيْدِ اللَّهِ ، عَنْ إِبْرَاهِيمَ ، عَنِ الأَسْوَدِ ، عَنْ عَائِشَةَ ، قَالَتْ كَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم يَجْتَهِدُ فِي الْعَشْرِ الأَوَاخِرِ مَا لاَ يَجْتَهِدُ فِي غَيْرِهَا . قَالَ أَبُو عِيسَى هَذَا حَدِيثٌ حَسَنٌ صَحِيحٌ غَرِيبٌ .
"The Messenger of Allah would struggle (to perform Salat more) during the last ten (nights) more than he would struggle in the rest of it."
Grade: Sahih (Darussalam)