Overall meaning : Allah. Exalted be He, says, mentioning the dire consequences that will be suffered by those who disdainfully turn away from the truth: No one does greater wrong than those who, when reminded of and admonished by their Lord’s clear revelations, turn away from them and forget the sins they have committed, through unbelief and acts of disobedience, without repenting of them and turning to Allah. We have cast veils over their hearts, for their stubbornly preferring blindness to guidance, so that they cannot understand what they are reminded of; We have also cast deafness in their ears so that they do not readily listen in such a way as to benefit from them; and if you, Muhammad, invite them to the path of truth, they will not respond to you, nor will they be ever guided to it.
The Almighty points out part of His immense mercy and bounteous grace: Your Lord, Muhammad, is the All-Forgiving, who forgives His servants’ sins when they repent; the All-Merciful to them. Were He to take to task those who wilfully turn away from His sings and revelations at once for the sins they commit, He would hasten their punishment in this very worldly life. Rather, they have an appointed time for their punishment which will not be delayed once it becomes due, and they will find no refuge from just punishment. Those ancient cities close to you, belonging to the people of Noah, Hud, Salih and Lot, among other past nations: We completely destroyed their inhabitants when they did wrong through their stubborn unbelief and disobedience; and for their destruction We set an appointed time.