[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 they have opposed God and His Messengers." For those who oppose God and His Messengers, God has prepared a severe retribution. 13 This-- taste it, and (know) that for the unbelievers is the chastisement of fire. 14 O ye who believe! When ye meet those who disbelieve in battle, turn not your backs to them. 15 Whoso turns his back that day to them, unless withdrawing to fight again or removing to join another host, he is laden with the burden of God's anger, and his refuge is Gehenna -- an evil homecoming! 16 Wherefore ye slew them not, but Allah slew them, and thou threwest not, when thou threwest, but Allah threw, in order that He might prove the believers with a goodly proving from Him. Verily Allah is Hearing, Knowing. 17 That (is the case); and (know) that Allah (it is) Who maketh weak the plan of disbelievers. 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