إِن هُوَ إِلّا ذِكرٌ لِلعالَمينَ

It is just a reminder for all the nations.

EXEGESIS

Dhikr (reminder) was explained in the commentary on verse 1. Just like there, some have interpreted it here too to mean sharaf (honour or nobility),^{‎[1]See for example Tibyan, 8/585.} for example: the Quran is naught but an honour for those who believe in it.^{‎[2]Tabrisi, 8/760.} However, reminder seems more appropriate.

ʿĀlamīn (nations) should be referring to mankind and jinn here,^{‎[3]Tabari, 23/120; Zamakhshari, 4/109; Qurtubi, 15/231.} especially considering the context of the previous verses. Or, it could mean the different nations of mankind.^{‎[4]Mizan, 17/228.} For a more detailed commentary on this word see the commentary on verse 1:2.

EXPOSITION

We are now brought back to the first verse of the surah. We are told again that everything that was said is a reminder, and this is the core function of the Quran.

[1] See for example Tibyan, 8/585.
[2] Tabrisi, 8/760.
[3] Tabari, 23/120; Zamakhshari, 4/109; Qurtubi, 15/231.
[4] Mizan, 17/228.