Jami at-Tirmidhi 170
Jami at-Tirmidhi · Book 2: The Book on Salat (Prayer) · Virtue Of Performing Salat at the Beginning Of Its Prescribed Time
Umm Farwah - and she was one of those who gave pledge of allegiance to the Prophet - narrated:
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 " .
"The Prophet was asked: 'Which deed is the best?' So he said: 'Salat in the beginning of its time.'"
Grade: Sahih (Darussalam)