O YOU who have attained to faith! What is amiss with you that, when you are called upon, "Go forth to war in God's cause," you cling heavily to the earth? Would you content yourselves with [the comforts of] this worldly life in preference to [the good of] the life to come? But the enjoyment of life in this world is but a paltry thing when compared with the life to come! 38 If you go not forth, He will chastise you with a painful chastisement, and instead of you He will substitute another people; and you will not hurt Him anything, for God is powerful over everything. 39 If you will not aid him, Allah certainly aided him when those who disbelieved expelled him, he being the second of the two, when they were both in the cave, when he said to his companion: Grieve not, surely Allah is with us. So Allah sent down His tranquillity upon him and strengthened him with hosts which you did not see, and made lowest the word of those who disbelieved; and the word of Allah, that is the highest; and Allah is Mighty, Wise. 40 Go forth, light and heavy! Struggle in God's way with your possessions and your selves; that is better for you, did you know. 41 (O Prophet), had the gain been close at hand, and easy the journey, they would surely have followed you; but hard was the journey and long the going. Even then they swear by God (and say): "If we had the strength we would surely have gone out with you." They are only ruining themselves, for God is aware they lie. 42