Overall meaning : All people, believers and unbelievers alike, Allah, Exalted be He, declares, will have different degrees of reward or punishment in the hereafter, which they deserve commensurate with their good or evil deeds, and that none of their actions whatsoever is hidden from Him: He keeps count of everyone’s actions, and according to their deeds, accordingly He will repay.
Your Lord, Muhammad, is self-sufficient—He is in need of nothing from anyone, people’s disobedience to Him will not harm Him in the least, nor will their obedience benefit Him at all—and He is full of mercy and compassion. If He wills, He could destroy you, O people, if you disobey Him and replace you with other people who will obey Him, even as He raised you from the seed of those before you.
The Almighty declares that the punishment He has threatened to inflict on those associating partners with Him for their unbelief will inevitably come, and that they will not be able to escape it.
Allah then instructs His Prophet, Muhammad, may Allah bless him and grant him peace, to say to the Quraysh idolaters among his people, if they refuse to obey him after calling them to His way: Continue doing what you have chosen for yourselves, and I will continue to do as my Lord has commanded me. You will know, when Allah inflicts His punishment on you, which of us is rightly-guided and will have the best outcome in this world and the hereafter. The wrongdoers will never succeed.