"Verily! As for those whom the angels take (in death) while they are wronging themselves (as they stayed among the disbelievers even though emigration was obligatory for them), they (angels) say (to them): In what (condition) were you?..."(V.4:97)
Authentic
hadith of Sahih al-Bukhari
Sahih al-Bukhari 4596
نَاسًا مِنَ الْمُسْلِمِينَ كَانُوا مَعَ الْمُشْرِكِينَ يُكَثِّرُونَ سَوَادَ الْمُشْرِكِينَ عَلَى رَسُولِ اللَّهِ صلى الله عليه وسلم يَأْتِي السَّهْمُ فَيُرْمَى بِهِ، فَيُصِيبُ أَحَدَهُمْ فَيَقْتُلُهُ أَوْ يُضْرَبُ فَيُقْتَلُ، فَأَنْزَلَ اللَّهُ {إِنَّ الَّذِينَ تَوَفَّاهُمُ الْمَلاَئِكَةُ ظَالِمِي أَنْفُسِهِمْ} الآيَةَ
Narrated Muhammad bin `Abdur-Rahman Abu Al-Aswad:
The people of Medina were forced to prepare an army (to fight against the people of Sham during the caliphate of `Abdullah bin Az-Zubair at Mecca), and I was enlisted in it; Then I met `Ikrima, the freed slave of Ibn `Abbas, and informed him (about it), and he forbade me strongly to do so (i.e. to enlist in that army), and then said, "Ibn `Abbas informed me that some Muslim people were with the pagans, increasing the number of the pagans against Allah's Messenger (ﷺ). An arrow used to be shot which would hit one of them (the Muslims in the company of the pagans) and kill him, or he would be struck and killed (with a sword)." Then Allah revealed:-- "Verily! as for those whom the angels take (in death) while they are wronging themselves (by staying among the disbelievers)" (4.97) Abu AlAswad also narrated it.
روى ابن عباس رضي الله عنهما أنه كان على عهد رسول الله صلى الله عليه وسلم جماعةٌ من المسلمين كانوا يقفون مع المشركين في القتال، يُكثِّرون عدد المشركين وجماعتهم، وهم ممن لم يهاجر، فيصيبهم السهم فيقتلهم، أو يُضربون فيُقتلون، فأنزل الله: {إن الذين توفاهم الملائكة ظالمي أنفسهم} الآية، ومع أنهم لا يوافقونهم في قلوبهم إلا أنهم كانوا ظالمين لأنفسهم؛ لأنهم زادوا المشركين قوة بوجودهم معهم.
بيان سبب نزول الآية الكريمة.
النهي عن مساعدة المشركين وتكثير أعدادهم، وأنه من ظلم النفس.