﴿ هَٰذَا هُدًۭى ۖ وَٱلَّذِينَ كَفَرُوا۟ بِـَٔايَٰتِ رَبِّهِمْ لَهُمْ عَذَابٌۭ مِّن رِّجْزٍ أَلِيمٌ ﴾

“[To pay heed to God’s signs and messages:] this is [the meaning of] guidance; on the other hand, for those who are bent on denying the truth of their Sustainer’s messages there is grievous suffering in store as an outcome of [their] vileness.”

(This) i.e. this Qur'an (is guidance) from error. (And those who disbelieve the revelations of their Lord) those who disbelieve in Muhammad (pbuh) and the Qur'an, i.e. al-Nadr Ibn al-Harith and his host, (for them there is a painful doom of wrath) for them there is a painful punishment.