Qur'an 4:82

أَفَلَا يَتَدَبَّرُونَ ٱلْقُرْءَانَ ۚ وَلَوْ كَانَ مِنْ عِندِ غَيْرِ ٱللَّهِ لَوَجَدُوا۟ فِيهِ ٱخْتِلَـٰفًا كَثِيرًا

“Then do they not reflect upon the Qur’ān? If it had been from [any] other than Allāh, they would have found within it much contradiction.”

An-Nisaa 4:82 · Saheeh International