﴿ وَلَقَدْ أَرْسَلْنَا نُوحًا إِلَىٰ قَوْمِهِۦ فَلَبِثَ فِيهِمْ أَلْفَ سَنَةٍ إِلَّا خَمْسِينَ عَامًۭا فَأَخَذَهُمُ ٱلطُّوفَانُ وَهُمْ ظَٰلِمُونَ ﴾

“And, indeed, [in times long past] We sent forth Noah unto his people, and he dwelt among them a thousand years bar fifty; and then the floods over­whelmed them while they were still lost in evildoing:”

And verily We sent Noah to his people when he was forty years of age or older and he remained among them a thousand-less-fifty years calling them to affirm God’s Oneness but they denied him; so the Flood engulfed them a deluge of water drifted against them rising above them and drowning them for they were wrongdoers idolaters.