And we are not going to be punished.
Allah's saying;
فَكَذَّبُوهُ فَأَهْلَكْنَاهُمْ
.
So they denied him, and We destroyed them.
meaning, they continued to disbelieve and stubbornly oppose Allah's Prophet Hud, so Allah destroyed them.
The means of their destruction has been described in more than one place in the Qur'an;
Allah sent against them a strong and furious wind, i.e., a fiercely blowing wind that was intensely cold. Thus the means of their destruction was suited to their nature, for they were the strongest and fiercest of people, so Allah overpowered them with something that was even stronger and fiercer than them, as Allah says;
أَلَمْ تَرَ كَيْفَ فَعَلَ رَبُّكَ بِعَادٍ
إِرَمَ ذَاتِ الْعِمَادِ
Have you not seen how your Lord dealt with `Ad of Iram Possessors of the pillars. (89;6-7)
This refers to the former `Ad, as Allah says;
وَأَنَّهُ أَهْلَكَ عَاداً الاٍّولَى
And that it is He Who destroyed the former `Ad. (53;50)
They were descendents of Iram bin Sam bin Nuh,
ذَاتِ الْعِمَادِ
(Possessors of the pillars),
They used to live among pillars.
Those who claim that Iram was a city take this idea from Israeli narrations, from the words of Ka`b and Wahb, but there is no real basis for that.
Allah says;
الَّتِى لَمْ يُخْلَقْ مِثْلُهَا فِى الْبِلَـدِ
The like of which were not created in the land. (89;8)
meaning, nothing like this tribe was created in terms of might, power and tyranny.
If what was meant was a city, it would have said,
"The like of which was not built in the land."
And Allah says;
فَأَمَّا عَادٌ فَاسْتَكْبَرُواْ فِى الاٌّرْضِ بِغَيْرِ الْحَقِّ وَقَالُواْ مَنْ أَشَدُّ مِنَّا قُوَّةً أَوَلَمْ يَرَوْاْ أَنَّ اللَّهَ الَّذِى خَلَقَهُمْ هُوَ أَشَدُّ مِنْهُمْ قُوَّةً وَكَانُواْ بِـَايَـتِنَا يَجْحَدُونَ
As for `Ad, they were arrogant in the land without right, and they said;"Who is mightier than us in strength!"
See they not that Allah Who created them was mightier in strength than them. And they used to deny Our Ayat! (41;15)
And Allah says;
وَأَمَّا عَادٌ فَأُهْلِكُوا بِرِيحٍ صَرْصَرٍ عَاتِيَةٍ
سَخَّرَهَا عَلَيْهِمْ سَبْعَ لَيَالٍ وَثَمَانِيَةَ أَيَّامٍ حُسُومًا
And as for `Ad, they were destroyed by a wind, Sarsar `Atiyah! Which Allah imposed on them for seven nights and eight days Husum, (in succession). (69;6-7)
meaning, consecutively (i.e., seven nights and eight days).
فَتَرَى الْقَوْمَ فِيهَا صَرْعَى كَأَنَّهُمْ أَعْجَازُ نَخْلٍ خَاوِيَةٍ
so that you could see men lying overthrown (destroyed), as if they were hollow trunks of date palms! (69;7)
means, they were left as headless bodies, because the wind would come and carry one of them, then drop him on his head, so that his brains were spilled out, his head was broken and he was thrown aside, as if they were uprooted stems of date-palms. They used to build fortresses in the mountains and caves, and they dug ditches half as deep as a man is tall, but that did not help them against the command of Allah at all.
إِنَّ أَجَلَ اللَّهِ إِذَا جَأءَ لَا يُوَخَّرُ
Verily, the term given by Allah, when it comes, cannot be delayed. (71;4)
Allah says here;
فَكَذَّبُوهُ فَأَهْلَكْنَاهُمْ
(So they denied him, and We destroyed them).
..
إِنَّ فِي ذَلِكَ لَايَةً
وَمَا كَانَ أَكْثَرُهُم مُّوْمِنِينَ