Jihad and fighting in Allah's cause

أَلَمْ تَرَ إِلَى ٱلْمَلَإِ مِنۢ بَنِىٓ إِسْرَٰٓءِيلَ مِنۢ بَعْدِ مُوسَىٰٓ إِذْ قَالُوا۟ لِنَبِىٍّ لَّهُمُ ٱبْعَثْ لَنَا مَلِكًا نُّقَـٰتِلْ فِى سَبِيلِ ٱللَّهِ ۖ قَالَ هَلْ عَسَيْتُمْ إِن كُتِبَ عَلَيْكُمُ ٱلْقِتَالُ أَلَّا تُقَـٰتِلُوا۟ ۖ قَالُوا۟ وَمَا لَنَآ أَلَّا نُقَـٰتِلَ فِى سَبِيلِ ٱللَّهِ وَقَدْ أُخْرِجْنَا مِن دِيَـٰرِنَا وَأَبْنَآئِنَا ۖ فَلَمَّا كُتِبَ عَلَيْهِمُ ٱلْقِتَالُ تَوَلَّوْا۟ إِلَّا قَلِيلًا مِّنْهُمْ ۗ وَٱللَّهُ عَلِيمٌۢ بِٱلظَّـٰلِمِينَ

Have you not considered the assembly of the Children of Israel after [the time of] Moses when they said to a prophet of theirs, "Send to us a king, and we will fight in the way of Allāh"? He said, "Would you perhaps refrain from fighting if battle was prescribed for you?" They said, "And why should we not fight in the cause of Allāh when we have been driven out from our homes and from our children?" But when battle was prescribed for them, they turned away, except for a few of them. And Allāh is Knowing of the wrongdoers.

۞ فَلْيُقَـٰتِلْ فِى سَبِيلِ ٱللَّهِ ٱلَّذِينَ يَشْرُونَ ٱلْحَيَوٰةَ ٱلدُّنْيَا بِٱلْـَٔاخِرَةِ ۚ وَمَن يُقَـٰتِلْ فِى سَبِيلِ ٱللَّهِ فَيُقْتَلْ أَوْ يَغْلِبْ فَسَوْفَ نُؤْتِيهِ أَجْرًا عَظِيمًا

So let those fight in the cause of Allāh who sell the life of this world for the Hereafter. And he who fights in the cause of Allāh and is killed or achieves victory - We will bestow upon him a great reward.