Overall meaning : Allah instructs His Prophet, Muhammad, may Allah bless him and grant him peace, to inform the idolaters who associate partners with Him that He has not forbidden what they themselves have made unlawful. He has only made unlawful indecent, shameful deeds, whether committed openly or in secret, and all manner of sin and wrongful oppression; and He has forbidden them to worship anyone or anything besides Him for which He has not sent down any authority at all and to falsely attribute to Him anything of which they have no knowledge whatsoever.
Every unbelieving nation, Allah states, has a specific time for punishment to be meted out to them. When the time that He has set for their destruction comes, they all perish, and they can neither delay it, nor advance it by even a single moment.