0 ye who believe! What is a matter with you, that, when ye are asked to go forth in the Cause of Allah, ye cling heavily to the earth? Do ye prefer the life of this world to the Hereafter ? But little is the comfort of this life, as compared with the Hereafter. Unless ye go forth, He will punish you with a grievous penalty, and put others in your place; but Him you would not harm in the least. For Allah hath power over all things. (9:38-39)