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Surah 7. Al-A'raf
Ayah 4 - 5
4وَكَم مِّن قَرْيَةٍ أَهْلَكْنَـٰهَا فَجَآءَهَا بَأْسُنَا بَيَـٰتًا أَوْ هُمْ قَآئِلُونَ
5فَمَا كَانَ دَعْوَىٰهُمْ إِذْ جَآءَهُم بَأْسُنَآ إِلَّآ أَن قَالُوٓا۟ إِنَّا كُنَّا ظَـٰلِمِينَ
[4-5] There leave been many habitations which We destroyed. Our scourge came upon them all of a sudden at night or at a time during the day where they were taking rest. When Our scourge overtook them, the only cry they could utter was "Indeed we were transgressors!"5
5That is, "You can learn a lesson from those communities that discarded the Guidance of Allah and followed the guidance of others, and consequently became so degenerate as to be a curse for the earth, which was cleansed of their filth by a scourge of Allah."
The words "Indeed we were transgressors" have been cited here to serve as a warning about two things. First, "It is absolutely useless to be sorry for and to confess one's error after the expiry of the term of respite given for its recompense." It is obvious that the individual and the community show utter lack of sense, if they waste the period of respite in negligence and turn a deaf ear to the warning and admonition of those who invite them to the Truth, and realize the horror of their conduct only when the scourge of Allah overtakes them. Secondly, "You yourselves have seen so many instances of individuals and communities. who were suddenly overtaken by the scourge of Allah, when they transgressed the bounds and reached the end of the term of their respite. You have also seen that after the scourge came upon them, there was no way of escape from it. When this has been the repeated verdict of history, why should a man repeat the same error over and over again, and wait for the ultimate end to offer repentance, when it cannot benefit in the least and can produce only grief and regret?