The Book of Jihad and Expeditions
32/7. Chapter:
It is recommended to pray for victory when meeting the enemy
Sahih Muslim
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 Thou wilt (defeat Muslims), there will be none on the earth to worship Thee.
Reference : Sahih Muslim 1743In-book reference : Book 32, Hadith 27USC-MSA web (English) reference : Book 19, Hadith 4318