صَحِيحُ مُسْلِمٍ
Sahih Muslim 1743
The Book of Jihad and Expeditions
It is recommended to pray for victory when meeting the enemy
وَحَدَّثَنِي حَجَّاجُ بْنُ الشَّاعِرِ، حَدَّثَنَا عَبْدُ الصَّمَدِ، حَدَّثَنَا حَمَّادٌ، عَنْ ثَابِتٍ، عَنْ أَنَسٍ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم كَانَ يَقُولُ يَوْمَ أُحُدٍ اللَّهُمَّ إِنَّكَ إِنْ تَشَأْ لاَ تُعْبَدْ فِي الأَرْضِ .
It is narrated on the authority of Anas that the Messenger of Allah (ﷺ) said on the day of the Battle of Uhud: O Allah, if You wilt (defeat Muslims), there will be none on the earth to worship You.
Sahih Muslim, 1743Sahihصحيح