﴿ وَسْـَٔلْهُمْ عَنِ ٱلْقَرْيَةِ ٱلَّتِى كَانَتْ حَاضِرَةَ ٱلْبَحْرِ إِذْ يَعْدُونَ فِى ٱلسَّبْتِ إِذْ تَأْتِيهِمْ حِيتَانُهُمْ يَوْمَ سَبْتِهِمْ شُرَّعًۭا وَيَوْمَ لَا يَسْبِتُونَ ۙ لَا تَأْتِيهِمْ ۚ كَذَٰلِكَ نَبْلُوهُم بِمَا كَانُوا۟ يَفْسُقُونَ ﴾

“And ask them about that town which stood by the sea: how its people would profane the Sabbath whenever their fish came to them, breaking the water's surface, on a day on which they ought to have kept Sabbath -because they would not come to them on other than Sabbath-days! Thus did We try them by means of their [own] iniquitous doings.”

The detailed discussion of the events contained in the above verses have been produced in Surah Al-Baqarah (under verses 58-60). Those interested may refer to those verses for details. The Holy Prophet ﷺ has been asked to warn the Israelites present in his time by reminding them the events related in these verses. The events referred to in these verses are clear and require no explanation.