The Romans
أَوَلَمْ يَتَفَكَّرُوا۟ فِىٓ أَنفُسِهِم ۗ مَّا خَلَقَ ٱللَّهُ ٱلسَّمَـٰوَٰتِ وَٱلْأَرْضَ وَمَا بَيْنَهُمَآ إِلَّا بِٱلْحَقِّ وَأَجَلٍ مُّسَمًّى ۗ وَإِنَّ كَثِيرًا مِّنَ ٱلنَّاسِ بِلِقَآئِ رَبِّهِمْ لَكَـٰفِرُونَ
Do they not contemplate within themselves? Allah has not created the heavens and the earth and what is between them except in truth and for a specified term. And indeed, many of the people, in [the matter of] the meeting with their Lord, are disbelievers.
Nearby ayahs help place verse 30:8 in sequence and meaning.
وَعْدَ ٱللَّهِ ۖ لَا يُخْلِفُ ٱللَّهُ وَعْدَهُۥ وَلَـٰكِنَّ أَكْثَرَ ٱلنَّاسِ لَا يَعْلَمُونَ
[It is] the promise of Allah. Allah does not fail in His promise, but most of the people do not know.
يَعْلَمُونَ ظَـٰهِرًا مِّنَ ٱلْحَيَوٰةِ ٱلدُّنْيَا وَهُمْ عَنِ ٱلْـَٔاخِرَةِ هُمْ غَـٰفِلُونَ
They know what is apparent of the worldly life, but they, of the Hereafter, are unaware.
أَوَلَمْ يَسِيرُوا۟ فِى ٱلْأَرْضِ فَيَنظُرُوا۟ كَيْفَ كَانَ عَـٰقِبَةُ ٱلَّذِينَ مِن قَبْلِهِمْ ۚ كَانُوٓا۟ أَشَدَّ مِنْهُمْ قُوَّةً وَأَثَارُوا۟ ٱلْأَرْضَ وَعَمَرُوهَآ أَكْثَرَ مِمَّا عَمَرُوهَا وَجَآءَتْهُمْ رُسُلُهُم بِٱلْبَيِّنَـٰتِ ۖ فَمَا كَانَ ٱللَّهُ لِيَظْلِمَهُمْ وَلَـٰكِن كَانُوٓا۟ أَنفُسَهُمْ يَظْلِمُونَ
Have they not traveled through the earth and observed how was the end of those before them? They were greater than them in power, and they plowed the earth and built it up more than they have built it up, and their messengers came to them with clear evidences. And Allah would not ever have wronged them, but they were wronging themselves.
ثُمَّ كَانَ عَـٰقِبَةَ ٱلَّذِينَ أَسَـٰٓـُٔوا۟ ٱلسُّوٓأَىٰٓ أَن كَذَّبُوا۟ بِـَٔايَـٰتِ ٱللَّهِ وَكَانُوا۟ بِهَا يَسْتَهْزِءُونَ
Then the end of those who did evil was the worst [consequence] because they denied the signs of Allah and used to ridicule them.