Protection of the Qur'an from corruption

وَمَا تَنَزَّلَتْ بِهِ ٱلشَّيَـٰطِينُ

And the devils have not brought it [i.e., the revelation] down.

إِنَّهُۥ لَقُرْءَانٌ كَرِيمٌ

Indeed, it is a noble Qur’ān.