And they say;"We are more in wealth and in children, and we are not going to be punished."
meaning, they were proud of their great wealth and great numbers of children, and they believed that this was a sign that Allah loved them and cared for them, and that if He gave them this in this world, He would not punish them in the Hereafter. This was too far-fetched.
Allah says;
أَيَحْسَبُونَ أَنَّمَا نُمِدُّهُمْ بِهِ مِن مَّالٍ وَبَنِينَ
نُسَارِعُ لَهُمْ فِى الْخَيْرَتِ بَل لاَّ يَشْعُرُونَ
Do they think that in wealth and children with which We enlarge them We hasten unto them with good things.
Nay, but they perceive not. (23;55-56)
فَلَ تُعْجِبْكَ أَمْوَلُهُمْ وَلَا أَوْلَـدُهُمْ إِنَّمَا يُرِيدُ اللَّهُ لِيُعَذِّبَهُمْ بِهَا فِي الْحَيَوةِ الدُّنْيَا وَتَزْهَقَ أَنفُسُهُمْ وَهُمْ كَـفِرُونَ
So, let not their wealth nor their children amaze you; in reality Allah's plan is to punish them with these things in the life of this world, and that their souls shall depart while they are disbelievers. (9;55)
and,
ذَرْنِى وَمَنْ خَلَقْتُ وَحِيداً
وَجَعَلْتُ لَهُ مَالاً مَّمْدُوداً
وَبَنِينَ شُهُوداً
وَمَهَّدتُّ لَهُ تَمْهِيداً
ثُمَّ يَطْمَعُ أَنْ أَزِيدَ
كَلَّ إِنَّهُ كان لاٌّيَـتِنَا عَنِيداً
سَأُرْهِقُهُ صَعُوداً
Leave Me Alone (to deal) with whom I created lonely. And then granted him resources in abundance. And children to be by his side. And made life smooth and comfortable for him. After all that he desires that I should give more.
Nay! Verily, he has been opposing Our Ayat. I shall oblige him to face a severe torment! (74;11-17)
And Allah has told us about the story of the owner of those two gardens, that he had wealth and crops and children, but that could not help him at all when all of that was taken from him in this world, before he reached the Hereafter.
Allah says here