Surah Ali 'Imran 3:156

يَـٰٓأَيُّهَا ٱلَّذِينَ ءَامَنُوا۟ لَا تَكُونُوا۟ كَٱلَّذِينَ كَفَرُوا۟ وَقَالُوا۟ لِإِخْوَٰنِهِمْ إِذَا ضَرَبُوا۟ فِى ٱلْأَرْضِ أَوْ كَانُوا۟ غُزًّى لَّوْ كَانُوا۟ عِندَنَا مَا مَاتُوا۟ وَمَا قُتِلُوا۟ لِيَجْعَلَ ٱللَّهُ ذَٰلِكَ حَسْرَةً فِى قُلُوبِهِمْ ۗ وَٱللَّهُ يُحْىِۦ وَيُمِيتُ ۗ وَٱللَّهُ بِمَا تَعْمَلُونَ بَصِيرٌ

O you who have believed, do not be like those who disbelieved and said about their brothers when they traveled through the land or went out to fight, "If they had been with us, they would not have died or have been killed," so Allāh makes that [misconception] a regret within their hearts. And it is Allāh who gives life and causes death, and Allāh is Seeing of what you do.

Translation: Saheeh International

Tafsir

O you who believe be not as the disbelievers that is as the hypocrites who say of their brothers that is regarding their affair when they travel in the land and then die or are on raiding campaigns ghuzzan ‘a raiding party’ is the plural of ghāzin and are then slain ‘Had they been with us they would not have died and …

Excerpt from Tafsir al-Jalalayn, commentary on 3:156, via Quran.com. The reader has the full commentary and 9 more tafsirs.