Surah 6:34
"Certainly messengers have been called liars before you, yet they patiently endured being called liars, and suffered harm, until Our help came to them. No one can change the words of God. Certainly some of the story has (already) come to you about the envoys (before you)."
6.34 – No one can change the words of God
This verse states that “there is no changer” of the words of Allah. The context here is the reassurance that Allah helped his messengers in the past. The statement that Allah’s word is unchangeable repeats in slightly different forms later in this sūra at verse 115 and also at 10.64 and 18.27. See a summary of these verses at 18.27.
- from The Quran with Christian Commentary: A Guide to Understanding the Scripture of Islam