When He caused calm to fall on you as a security from Him and sent down upon you water from the cloud that He might thereby purify you, and take away from you the uncleanness of the Shaitan, and that He might fortify your hearts and steady (your) footsteps thereby. 11 And when Allah revealed to the angels, saying: 'I shall be with you. Give courage to the believers. I shall cast terror into the hearts of the unbelievers. Strike them above the necks, smite their finger tips' 12 That is because they opposed Allah and His messenger. Whoso opposeth Allah and His messenger, (for him) lo! Allah is severe in punishment. 13 That is your punishment, taste it then; and know that for those who deny the truth there is the punishment of the Fire. 14 O you who believe! when you meet those who disbelieve marching for war, then turn not your backs to them. 15 Whoso on that day turneth his back to them, unless manoeuvring for battle or intent to join a company, he truly hath incurred wrath from Allah, and his habitation will be hell, a hapless journey's end. 16 And you did not kill them, but it was Allah who killed them. And you threw not, [O Muhammad], when you threw, but it was Allah who threw that He might test the believers with a good test. Indeed, Allah is Hearing and Knowing. 17 That for you; and that God weakens the unbelievers' guile. 18 If you [disbelievers] seek the victory - the defeat has come to you. And if you desist [from hostilities], it is best for you; but if you return [to war], We will return, and never will you be availed by your [large] company at all, even if it should increase; and [that is] because Allah is with the believers. 19