The Messenger of Allah ﷺ was carrying the earth with us on the Day of Ahzab and the whiteness of his belly had been covered with earth. (While engaged in this toil) he was reciting: By God, if Thou hadst not guided us We would have neither been guided aright nor practised charity, Nor offered prayers. Descend on us peace and tranquillity. Behold I these people (the Meccans) refused to follow us. According to another version, he recited: The chieftains (of the tribes) refused to follow us When they contemplated mischief, we rejected it. And with this (verse) he would raise his voice. (Using translation from Muslim 1803a)   

سَمِعْتُ الْبَرَاءَ بْنَ عَازِبٍ يَقُولُ كَانَ رَسُولُ اللَّهِ ﷺ يَنْقُلُ مَعَنَا التُّرَابَ يَوْمَ الْأَحْزَابِ وَقَدْ وَارَى التُّرَابُ بَيَاضَ إِبِطَيْهِ وَهُوَ يَقُولُ «اللَّهُمَّ لَوْلَا أَنْتَ مَا اهْتَدَيْنَا وَلَا تَصَدَّقْنَا وَلَا صَلَّيْنَا فَأَنْزِلَنَّ سَكِينَةً عَلَيْنَا وَثَبِّتِ الْأَقْدَامَ إِنْ لَاقَيْنَا إِنَّ الْأُلَى قَدْ بَغَوْا عَلَيْنَا وَإِنْ أَرَادُوا فِتْنَةً أَبَيْنَا» وَيَرْفَعُ بِهَا صَوْتَهُ