[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 the angels, "Verily, I am with you, so keep firm those who have believed. I will cast terror into the hearts of those who have disbelieved, so strike them over the necks, and smite over all their fingers and toes." 12 That was because they defied God and His Messenger. He who defies God and His Messenger shall be severely punished by God. 13 'That for you, so taste it, the punishment of the Fire is for the unbelievers' 14 Believers, do not retreat when facing the marching army of the unbelievers, for no believer will turn back at that time except for strategic reasons or to join another band. 15 And whoever turns his back to them on such a day - unless it be a stratagem of war, or to retreat to a troop (of his own), - he indeed has drawn upon himself wrath from Allah. And his abode is Hell, and worst indeed is that destination! 16 It was not you (believers) but God who slew the pagans. It was not you (Muhammad) but God who threw dust at them. He did this as a favorable test for the believers. God is All-hearing and All-knowing. 17 that is what happened, and God will surely undermine the design of those who deny the truth. 18 If you have been praying for victory, [O believers] - victory has now indeed come unto you. And if you abstain [from sinning,] it will be for your own good; but if you revert to it, We shall revoke [Our promise of aid] - and never will your community be of any avail to you, however great its numbers: for, behold, God is [only] with those who believe! 19