[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 is the torment, so taste it, and surely for the disbelievers is the torment of the Fire. 14 O YOU who have attained to faith! When you meet in battle those who are bent on denying the truth, advancing in great force, do not turn your backs on them: 15 And whosoever turneth his back to them on such a day, unless it be swerving to a fight or wriggling round to company, hath surely drawn upon himself indignation from Allah, and his resort is Hell - an evil destination! 16 And yet, [O believers,] it was not you who slew the enemy, but it was God who slew them; and it was not thou who cast [terror into them, O Prophet,] when thou didst cast it, but it was God who cast it: and [He did all this] in order that He might test the believers by a goodly test of His Own ordaining. Verily, God is all-hearing, all-knowing! 17 Allah will surely weaken the guile of the unbelievers. 18 If victory you are seeking, victory has already come upon you; and if you give over, it is better for you. But if you return, We shall return, and your host will avail you nothing though it be numerous; and that God is with the believers. 19