Surah At-Takwir (The Overthrowing): Verse 28

This phrase is an apposition (badal) to "the worlds" (al-'alamin). The implied structure is: "It is nothing but a reminder for any of you who wills to go straight."

The benefit of this apposition is that those who will to be upright (by entering Islam) are the ones who benefit from the Reminder (the Quran). It is as if no one else is admonished by it. The meaning is that the Quran is only beneficial to those who will to be upright.

Then, He clarified that the will to be upright is dependent upon the Will of God: