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 do not go forth to war [in God's cause,] He will chastise you with grievous chastisement, and will place another people in your stead - whereas you shall in no wise harm Him: for, God has the power to will anything. 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 Were it a gain at hand or a short journey, they would have surely followed you, but the distance seemed too far to them. Still they will swear by Allah: "If only we could, we would surely have gone forth with you." They merely bring ruin upon themselves. Allah knows well that they are liars. 42