Sahih Bukhari Volume 9, Book 94, Hadith 7238

حَدَّثَنَا عَبْدَانُ، أَخْبَرَنِي أَبِي، عَنْ شُعْبَةَ، حَدَّثَنَا أَبُو إِسْحَاقَ، عَنِ الْبَرَاءِ بْنِ عَازِبٍ، قَالَ كَانَ النَّبِيُّ صلى الله عليه وسلم يَنْقُلُ مَعَنَا التُّرَابَ يَوْمَ الأَحْزَابِ، وَلَقَدْ رَأَيْتُهُ وَارَى التُّرَابُ بَيَاضَ بَطْنِهِ يَقُولُ ‏"‏ لَوْلاَ أَنْتَ مَا اهْتَدَيْنَا نَحْنُ، وَلاَ تَصَدَّقْنَا وَلاَ صَلَّيْنَا، فَأَنْزِلَنْ سَكِينَةً عَلَيْنَا، إِنَّ الأُلَى وَرُبَّمَا قَالَ الْمَلاَ قَدْ بَغَوْا عَلَيْنَا، إِذَا أَرَادُوا فِتْنَةً أَبَيْنَا ‏"‏ أَبَيْنَا يَرْفَعُ بِهَا صَوْتَهُ‏

Narrated By Al-Bara' bin 'Azib : The Prophet was carrying earth with us on the day of the battle of Al-Ahzab (confederates) and I saw that the dust was covering the whiteness of his abdomen, and he (the Prophet) was saying, "(O Allah) ! Without You, we would not have been guided, nor would we have given in charity, nor would we have prayed. So (O Allah!) please send tranquillity (Sakina) upon us as they, (the chiefs of the enemy tribes) have rebelled against us. And if they intend affliction (i.e. want to frighten us and fight against us) then we would not (flee but withstand them). And the Prophet used to raise his voice with it.