When they are invited to GOD and His messenger to judge among them, some of them get upset. In fact, it is they who are unjust. These are the winners. Those who obey GOD and His messenger, and reverence GOD and observe Him, these are the triumphant ones. They swear by GOD, solemnly, that if you commanded them to mobilize, they would mobilize.
Obedience is an obligation.
GOD is fully Cognizant of everything you do. If they refuse, then he is responsible for his obligations, and you are responsible for your obligations. If you obey him, you will be guided. Those who disbelieve after this are the truly wicked. This is to be done in three instances - before the Dawn Prayer, at noon when you change your clothes to rest, and after the Night Prayer.