Quran 9:41 — Ultimatum (Bara'ah)

You shall readily mobilize, light or heavy, and strive with your money and your lives in the cause of GOD. This is better for you, if you only knew.

[9:40] If you fail to support him (the messenger), GOD has already supported him. Thus, when the disbelievers chased him, and he was one of two in the cave, he said to his friend, "Do not worry; GOD is with us." GOD then sent down contentment and security upon him, and supported him with invisible soldiers. He made the word of the disbelievers lowly. GOD's word reigns supreme. GOD is Almighty, Most Wise.

[9:42] If there were a quick material gain, and a short journey, they would have followed you. But the striving is just too much for them. They will swear by GOD: "If we could, we would have mobilized with you." They thus hurt themselves, and GOD knows that they are liars.