َ فَمَا لَهُمْ لَا يُؤْمِنُونَ ﴿۲۰﴾ وَإِذَا قُرِئَ عَلَيْهِمُ الْقُرْآنُ لَا يَسْجُدُونَ۩ ࣛ ﴿۲۱﴾ بَلِ الَّذِينَ كَفَرُوا يُكَذِّبُونَ ﴿۲۲﴾ وَاللَّهُ أَعْلَمُ بِمَا يُوعُونَ ﴿۲۳﴾ فَبَشِّرْهُمْ بِعَذَابٍ أَلِيمٍ ﴿۲۴﴾ إِلَّا الَّذِينَ آمَنُوا وَعَمِلُوا الصَّالِحَاتِ لَهُمْ أَجْرٌ غَيْرُ مَمْنُونٍ ﴿۲۵﴾

﴾20﴿ Famaa lahum laa yu'minoon
﴾21﴿ Wa izaa quri'a 'alaihimul Quraanu laa yasjudoon (make sajda)
﴾22﴿ Balil lazeena kafaroo yukazziboon
﴾23﴿ Wallaahu a'lamu bimaa yoo'oon
﴾24﴿ Fabashshirhum bi'azaabin aleem
﴾25﴿ Illal lazeena aamanoo wa 'amilus saalihaati lahum ajrun ghairu mamnoon

﴾20﴿ So what is the matter with them that they do not believe
﴾21﴿ And when the Quran is recited to them, they do not prostrate
﴾22﴿ Rather, those who disbelieve deny the truth
﴾23﴿ And Allah, the Exalted, is fully aware of what they conceal in their hearts
﴾24﴿ So give them glad tidings of a painful punishment
﴾25﴿ Except for those who believe and do righteous deeds; for them is a never-ending reward

[20,21] These are rebukes through the mention of four states of the deniers.
In the first verse, there is a reference to belief-related disbelief and shirk (associating partners with Allah),
and in the second, a reference to action-based disbelief and shirk.
(لَا يَسْجُدُونَ) — means they do not devote their prostration solely to Allah the Exalted; rather, they associate others with Him in worship.
Or, sujūd here may refer to prayer (ṣalāh) in general — mentioning a part (sujūd) but intending the whole (ṣalāh).
Most scholars are of the opinion that this is a verse of sajdah (prostration),
because Allah the Exalted rebuked those who do not prostrate, so it is appropriate for the believer to perform sujūd at this point.
[22,23] This too describes the states of the deniers.
[24,25] In the first verse, there is a warning (takhwīf), introduced with fa to show it is a consequence of the previous actions,
and the mention of glad tidings is made mockingly, as a form of sarcasm toward the deniers.
In the second verse, the glad tidings are genuine — a true promise for the righteous.