عَنْ أُمِّ فَرْوَةَ رَضِيَ اللَّهُ عَنْهَا وَكَانَتْ قَدْ بَايَعَتْ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ قَالَتْ: سُئِلَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ عَنْ أَفْضَلِ الْعَمَلِ، فَقَالَ: ((الصَّلَاةُ لِأَوَّلِ وَقْتِهَا))
Sayyida Umm Farwah (may Allah be pleased with her), who had pledged allegiance to the Messenger of Allah (peace and blessings be upon him), says that the Messenger of Allah (peace and blessings be upon him) was asked about the most virtuous deed. He (peace and blessings be upon him) replied: To perform the prayer at its earliest time.