Surah Al-Baqarah 2:194

ٱلشَّهْرُ ٱلْحَرَامُ بِٱلشَّهْرِ ٱلْحَرَامِ وَٱلْحُرُمَـٰتُ قِصَاصٌ ۚ فَمَنِ ٱعْتَدَىٰ عَلَيْكُمْ فَٱعْتَدُوا۟ عَلَيْهِ بِمِثْلِ مَا ٱعْتَدَىٰ عَلَيْكُمْ ۚ وَٱتَّقُوا۟ ٱللَّهَ وَٱعْلَمُوٓا۟ أَنَّ ٱللَّهَ مَعَ ٱلْمُتَّقِينَ

[Battle in] the sacred month is for [aggression committed in] the sacred month, and for [all] violations is legal retribution. So whoever has assaulted you, then assault him in the same way that he has assaulted you. And fear Allāh and know that Allāh is with those who fear Him.

Translation: Saheeh International

Tafsir

The sacred month in return for the sacred month therefore just as they fight you during it kill them during it a response to the Muslims’ consideration of the momentous nature of this matter; …

Excerpt from Tafsir al-Jalalayn, commentary on 2:194, via Quran.com. The reader has the full commentary and 9 more tafsirs.