Surah Al Furqan Tafseer

وَقَوْمَ نُوحٍ لَّمَّا كَذَّبُوا الرُّسُلَ

And Nuh's people, when they denied the Messengers,

although Allah sent only Nuh to them, and he stayed among them for 950 years, calling them to Allah and warning them of His punishment,

(And none believed with him, except a few. (11:40)

For this reason Allah

drowned them all and left no one among the sons of Adam alive on earth apart from those who boarded the boat,

وَجَعَلْنَاهُمْ لِلنَّاسِ ايَةً

and We made them a sign for mankind.

meaning a lesson to be learned.

This is like the Ayah,

إِنَّا لَمَّا طَغَا الْمَأءُ حَمَلْنَـكُمْ فِى الْجَارِيَةِ

لِنَجْعَلَهَا لَكُمْ تَذْكِرَةً وَتَعِيَهَأ أُذُنٌ وَعِيَةٌ

Verily, when the water rose beyond its limits, We carried you in the boat. That We might make it a remembrance for you, and the keen ear may understand it. (69:11-12)

which means:`We left for you ships that you ride upon to travel across the depths of the seas, so that you may remember the blessing of Allah towards you when He saved you from drowning, and made you the descendants of those who believed in Allah and followed His commandments.'

..

وَأَعْتَدْنَا لِلظَّالِمِينَ عَذَابًا أَلِيمًا

And We have prepared a painful torment for the wrongdoers.

Allah further tells