Hadith 170
Chapter 13: Virtue Of Performing Salat at the Beginning Of Its Prescribed Time - كتاب الصلاة
حَدَّثَنَا أَبُو عَمَّارٍ الْحُسَيْنُ بْنُ حُرَيْثٍ، حَدَّثَنَا الْفَضْلُ بْنُ مُوسَى، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ الْعُمَرِيِّ، عَنِ الْقَاسِمِ بْنِ غَنَّامٍ، عَنْ عَمَّتِهِ أُمِّ فَرْوَةَ، وَكَانَتْ، مِمَّنْ بَايَعَتِ النَّبِيَّ صلى الله عليه وسلم قَالَتْ سُئِلَ النَّبِيُّ صلى الله عليه وسلم أَىُّ الأَعْمَالِ أَفْضَلُ قَالَ " الصَّلاَةُ لأَوَّلِ وَقْتِهَا " .
Umm Farwah - and she was one of those who gave pledge of allegiance to the Prophet - narrated:
"The Prophet was asked: 'Which deed is the best?' So he said: 'Salat in the beginning of its time.'"
Reference : Jami` at-Tirmidhi 170
In-book reference : Book 2, Hadith 22