Aal-i-Imraan 3:154

Then He sent down tranquility upon you after distress: a slumber overtaking a group of you[70], while another group[71] cared only about themselves, having false thoughts about Allah, the untrue thoughts of ignorance, saying, “Do we have any say in the matter?” Say, “All matters belong to Allah.” They conceal in their hearts what they do not reveal to you. They say, “If we had any say in the matter, none of us would have been killed here.” Say, “Even if you had been in your homes, those among you who were destined to be killed would have come out to their killing places.” But Allah did this so that He may test your inner thoughts and distinguish what is in your hearts. For Allah is All-Knowing of what is in the hearts.

[70] The real believers.
[71] The hypocrites.

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 Allāh 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 Allāh." They conceal within themselves what they will not reveal to you. They say, "If there was anything we could have done in the matter, we [i.e., 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 Allāh might test what is in your breasts and purify what is in your hearts. And Allāh is Knowing of that within the breasts.

154. Then after the distress, He sent down security for you. Slumber overtook a party of you, while another party was thinking about themselves (as how to save their ownselves, ignoring the others and the Prophet صلى الله عليه وسلم) and thought wrongly of Allâh - the thought of ignorance. They said, "Have we any part in the affair?" Say (O Muhammad صلى الله عليه وسلم): "Indeed the affair belongs wholly to Allâh." They hide within themselves what they dare not reveal to you, saying: "If we had anything to do with the affair, none of us would have been killed here." Say: "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 Allâh might test what is in your breasts; and to purify [30] that which was in your hearts (sins), and Allâh is All-Knower of what is in (your) breasts.

[30] (V.3:154) The Arabic word yumahhis has three meanings: (1) To test, (2) To purify, (3) To get rid of (TafsirAl-Qurtubi ).

Then, after grief, He sent down security for you. As slumber did it overcome a party of you, while (the other) party, who were anxious on their own account, thought wrongly of Allah, the thought of ignorance. They said: Have we any part in the cause? Say (O Muhammad): The cause belongeth wholly to Allah. They hide within themselves (a thought) which they reveal not unto thee, saying: Had we had any part in the cause we should not have been slain here. Say: Even though ye had been in your houses, those appointed to be slain would have gone forth to the places where they were to lie. (All this hath been) in order that Allah might try what is in your breasts and prove what is in your hearts. Allah is Aware of what is hidden in the breasts (of men).