Translation of the verse 154 from Surah al-‘Imran : Number of verses 200 - - page 70 - Part 4.
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 SAW) and thought wrongly of Allah - the thought of ignorance. They said, "Have we any part in the affair?" Say you (O Muhammad SAW): "Indeed the affair belongs wholly to Allah." 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 Allah might test what is in your breasts; and to Mahis that which was in your hearts (sins), and Allah is All-Knower of what is in (your) breasts.
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.
(3:154) Then, after inflict-ing this grief, He sent down an inner peace upon you - a sleep which overtook some of you. *112 Those who were concerned merely about themselves, entertaining false notions about Allah - the notions of the Age of Ignorance - asked: 'Have we any say in the matter?' Tell them: 'Truly, all power of decision rests solely with Allah.' Indeed, they conceal in their hearts what they would not reveal to you, saying: 'If we had any power of decision, we would not have been slain here.' Say: 'Even if you had been in your houses, those for whom slaying had been appointed would have gone forth to the places where they were to be slain.' And all this happened so that Allah might test your secret thoughts and purge your hearts of all impurities. Allah knows well what is in the breasts of men.
*112). A strange phenomenon was then experienced by certain Muslim soldiers. Abu Talhah, who took part in the battle, states that the Muslims were seized by such drowsiness that their swords were slipping from their hands. (For several Traditions stating this incident, including one related by Abu Talhah, see Waqidi, Maghazi, vol. 1, pp. 295-6 - Ed.)