ALI 'IMRAN — Ayat 154
ثُمَّ أَنزَلَ عَلَيْكُم مِّن بَعْدِ الْغَمِّ أَمَنَةً نُّعَاسًا يَغْشَى طَآئِفَةً مِّنكُمْ وَطَآئِفَةٌ قَدْ أَهَمَّتْهُمْ أَنفُسُهُمْ يَظُنُّونَ بِاللّهِ غَيْرَ الْحَقِّ ظَنَّ الْجَاهِلِيَّةِ يَقُولُونَ هَل لَّنَا مِنَ الأَمْرِ مِن شَيْءٍ قُلْ إِنَّ الأَمْرَ كُلَّهُ لِلَّهِ يُخْفُونَ فِي أَنفُسِهِم مَّا لاَ يُبْدُونَ لَكَ يَقُولُونَ لَوْ كَانَ لَنَا مِنَ الأَمْرِ شَيْءٌ مَّا قُتِلْنَا هَاهُنَا قُل لَّوْ كُنتُمْ فِي بُيُوتِكُمْ لَبَرَزَ الَّذِينَ كُتِبَ عَلَيْهِمُ الْقَتْلُ إِلَى مَضَاجِعِهِمْ وَلِيَبْتَلِيَ اللّهُ مَا فِي صُدُورِكُمْ وَلِيُمَحَّصَ مَا فِي قُلُوبِكُمْ وَاللّهُ عَلِيمٌ بِذَاتِ الصُّدُورِ
Then after distress, He sent down upon you security [in the form of] drowsiness, overcoming a faction of you, while another faction worried about themselves, thinking of Allah other than the truth - the thought of ignorance, saying, "Is there anything for us [to have done] in this matter?" Say, "Indeed, the matter belongs completely to Allah ." They conceal within themselves what they will not reveal to you. They say, "If there was anything we could have done in the matter, some of us would not have been killed right here." Say, "Even if you had been inside your houses, those decreed to be killed would have come out to their death beds." [It was] so that Allah might test what is in your breasts and purify what is in your hearts. And Allah is Knowing of that within the breasts.
Tafsir Ibnu Katsir
ثُمَّ أَنزَلَ عَلَيْكُمْ مِّن بَعْدِ الْغَمِّ أَمَنَةً نُّعَاساً يَغْشَى طَآئِفَةً مِّنْكُمْ وَطَآئِفَةٌ قَدْ أَهَمَّتْهُمْ أَنْفُسُهُمْ يَظُنُّونَ بِاللَّهِ غَيْرَ الْحَقِّ ظَنَّ الْجَـهِلِيَّةِ يَقُولُونَ هَل لَّنَا مِنَ الاٌّمْرِ مِن شَىْءٍ قُلْ إِنَّ الاٌّمْرَ كُلَّهُ للَّهِ يُخْفُونَ فِى أَنْفُسِهِم مَّا لاَ يُبْدُونَ لَكَ يَقُولُونَ لَوْ كَانَ لَنَا مِنَ الاٌّمْرِ شَىْءٌ مَّا قُتِلْنَا هَـهُنَا قُل لَّوْ كُنتُمْ فِى بُيُوتِكُمْ لَبَرَزَ الَّذِينَ كُتِبَ عَلَيْهِمُ الْقَتْلُ إِلَى مَضَاجِعِهِمْ وَلِيَبْتَلِىَ اللَّهُ مَا فِى صُدُورِكُمْ وَلِيُمَحِّصَ مَا فِى قُلُوبِكُمْ وَاللَّهُ عَلِيمٌ بِذَاتِ الصُّدُورِ - إِنَّ الَّذِينَ تَوَلَّوْاْ مِنكُمْ يَوْمَ الْتَقَى الْجَمْعَانِ إِنَّمَا اسْتَزَلَّهُمُ الشَّيْطَـنُ بِبَعْضِ مَا كَسَبُواْ وَلَقَدْ عَفَا اللَّهُ عَنْهُمْ إِنَّ اللَّهَ غَفُورٌ حَلِيمٌ
154. Then after the distress, He sent down security for you. Slumber overtook a party of you, while another party was thinking about themselves and thought wrongly of Allah -- the thought of ignorance. They said, â€Have we any part in the affair'' Say: â€Indeed the affair belongs wholly to Allah.'' They hide within themselves what they dare not reveal to you, saying: â€If we had anything to do with the affair, none of us would have been killed here.'' Say: â€Even if you had remained in your homes, those for whom death was decreed would certainly have gone forth to the place of their death,'' but that Allah might test what is in your breasts; and to purify that which was in your hearts (sins), and Allah is All-Knower of what is in the breasts. 155. Those of you who turned back on the day the two hosts met, Shaytan only caused them to err because of some of what they had earned. But Allah, indeed, has forgiven them. Surely, Allah is Oft-Forgiving, Most Forbearing.  Allah reminds His servants of His favor when He sent down on them tranquillity and slumber that overcame them while they were carrying their weapons and feeling distress and grief. In this case, slumber is a favor and carries meanings of calmness and safety. For instance, Allah said in Surat Al-Anfal about the battle of Badr, Â