Read Ruku 447 of the Quran

قُل لِّلْمُخَلَّفِينَ مِنَ ٱلْأَعْرَابِ سَتُدْعَوْنَ إِلَىٰ قَوْمٍ أُو۟لِى بَأْسٍۢ شَدِيدٍۢ تُقَـٰتِلُونَهُمْ أَوْ يُسْلِمُونَ ۖ فَإِن تُطِيعُوا۟ يُؤْتِكُمُ ٱللَّهُ أَجْرًا حَسَنًۭا ۖ وَإِن تَتَوَلَّوْا۟ كَمَا تَوَلَّيْتُم مِّن قَبْلُ يُعَذِّبْكُمْ عَذَابًا أَلِيمًۭا ﴿١٦﴾

Say to those who remained behind of the bedouins, "You will be called to [face] a people of great military might; you may fight them, or they will submit. So if you obey, Allah will give you a good reward; but if you turn away as you turned away before, He will punish you with a painful punishment."

لَّيْسَ عَلَى ٱلْأَعْمَىٰ حَرَجٌۭ وَلَا عَلَى ٱلْأَعْرَجِ حَرَجٌۭ وَلَا عَلَى ٱلْمَرِيضِ حَرَجٌۭ ۗ وَمَن يُطِعِ ٱللَّهَ وَرَسُولَهُۥ يُدْخِلْهُ جَنَّـٰتٍۢ تَجْرِى مِن تَحْتِهَا ٱلْأَنْهَـٰرُ ۖ وَمَن يَتَوَلَّ يُعَذِّبْهُ عَذَابًا أَلِيمًۭا ﴿١٧﴾

There is not upon the blind any guilt or upon the lame any guilt or upon the ill any guilt [for remaining behind]. And whoever obeys Allah and His Messenger - He will admit him to gardens beneath which rivers flow; but whoever turns away - He will punish him with a painful punishment.