Surah An-Nisa 4:84

فَقَـٰتِلْ فِى سَبِيلِ ٱللَّهِ لَا تُكَلَّفُ إِلَّا نَفْسَكَ ۚ وَحَرِّضِ ٱلْمُؤْمِنِينَ ۖ عَسَى ٱللَّهُ أَن يَكُفَّ بَأْسَ ٱلَّذِينَ كَفَرُوا۟ ۚ وَٱللَّهُ أَشَدُّ بَأْسًا وَأَشَدُّ تَنكِيلًا

So fight, [O Muḥammad], in the cause of Allāh; you are not held responsible except for yourself. And encourage the believers [to join you] that perhaps Allāh will restrain the [military] might of those who disbelieve. And Allāh is greater in might and stronger in [exemplary] punishment.

Translation: Saheeh International

Tafsir

So fight O Muhammad (s) in the way of God; you are charged only with yourself so do not be concerned with their failing to join you the meaning being fight even if you are on your own for you have been promised victory. And urge on the believers incite them to fight and make them desire it; …

Excerpt from Tafsir al-Jalalayn, commentary on 4:84, via Quran.com. The reader has the full commentary and 9 more tafsirs.