عَنْ أَبِي سَعِيدٍ الْخُدْرِيِّ رَضِيَ اللَّهُ عَنْهُ قَالَ قُلْنَا يَوْمَ الْخَنْدَقِ يَا رَسُولَ اللَّهِ هَلْ مِنْ شَيْءٍ نَقُولُهُ فَقَدْ بَلَغَتِ الْقُلُوبُ الْحَنَاجِرَ قَالَ نَعَمْ اللَّهُمَّ اسْتُرْ عَوْرَاتِنَا وَآمِنْ رَوْعَاتِنَا قَالَ فَضَرَبَ اللَّهُ عَزَّ وَجَلَّ وُجُوهَ أَعْدَائِهِ بِالرِّيحِ فَهَزَمَهُمُ اللَّهُ عَزَّ وَجَلَّ بِالرِّيحِ
It is narrated from Sayyiduna Abu Sa'id Khudri (may Allah be pleased with him), he says: On the day of the battle, we said: O Messenger of Allah! Is there any supplication, our hearts have reached our mouths? The Prophet (peace and blessings be upon him) said: Absolutely, say: "Allahumma astur 'awratina, wa amin raw'atina" (O Allah! Conceal our faults and grant us security from our fears). Then Allah Almighty sent such a wind upon the enemies that through that wind He defeated them.