Believers! What is amiss with you that when it is said to you: "March forth in the cause of Allah," you cling heavily to the earth? Do you prefer the worldly life to the Hereafter? Know well that all the enjoyment of this world, in comparison with the Hereafter, is trivial. 38 If you do not march for His cause, He will afflict your with a painful punishment and replace you by another nation and your (destruction) will not harm Him at all. God has power over all things. 39 If you do not support him [Muhammad], know that God did support him when those who denied the truth expelled him when the two of them were in the cave, he [Muhammad] told his companion, "Do not worry; for God is with us." So God sent His tranquillity down on him and aided him with forces invisible to you and placed the word of those who disbelieved lowest, while God's word remained supreme. God is powerful and wise. 40 March forth light and heavy and strive hard with your riches and your lives in the way of Allah; that is the best for you, if ye have knowledge. 41 Had there been [a prospect of] immediate gain, and an easy journey, they would certainly have followed thee, [O Prophet:] but the distance was too great for them. And yet, [after your return, O believers,] they will swear by God, "Had we been able to do so, we would certainly have set out with you!" - [and by thus falsely swearing] they will be destroying their own selves: for God knows indeed that they are lying! 42