[Remember how it was] when He caused inner calm to enfold you, as an assurance from Him, and sent down upon you water from the skies, so that He might purify you thereby and free you from Satan's unclean whisperings and strengthen your hearts and thus make firm your steps. 11 [Remember] when your Lord inspired to the angels, "I am with you, so strengthen those who have believed. I will cast terror into the hearts of those who disbelieved, so strike [them] upon the necks and strike from them every fingertip." 12 That is because they opposed Allah and His Messenger. And whoever opposes Allah and His Messenger - indeed, Allah is severe in penalty. 13 We will say to them, "Endure the torment (as a consequence of your evil deeds); the unbelievers deserve nothing better than (the torment) of fire." 14 Believers, whenever you encounter a hostile force of unbelievers, do not turn your backs to them in flight. 15 (Whoever deserts the believers) will incur the wrath of God and will dwell in hell, a terrible dwelling. 16 So you did not slay them, but it was Allah Who slew them, and you did not smite when you smote (the enemy), but it was Allah Who smote, and that He might confer upon the believers a good gift from Himself; surely Allah is Hearing, Knowing. 17 This, and that Allah is the weakener of the struggle of the unbelievers. 18 (Tell the unbelievers:) 'If you have sought a judgement, then surely a judgement has come to you. And if you desist from disobedience, it is all the better for you. But if you revert to your mischief, We will again chastise you; and your host, howsoever numerous, will never be of any avail to you. Know well, Allah is with the believers.' 19