Surah Fussilat, ayah 44

وَلَوۡ جَعَلۡنَٰهُ قُرۡءَانًا أَعۡجَمِيّٗا لَّقَالُواْ لَوۡلَا فُصِّلَتۡ ءَايَٰتُهُۥٓۖ ءَا۬عۡجَمِيّٞ وَعَرَبِيّٞۗ قُلۡ هُوَ لِلَّذِينَ ءَامَنُواْ هُدٗى وَشِفَآءٞۚ وَٱلَّذِينَ لَا يُؤۡمِنُونَ فِيٓ ءَاذَانِهِمۡ وَقۡرٞ وَهُوَ عَلَيۡهِمۡ عَمًىۚ أُوْلَٰٓئِكَ يُنَادَوۡنَ مِن مَّكَانِۭ بَعِيدٖ ٤٤

Walaw ja'alnāhu qur'ānan a'jamiyyal laqālū lawlā fussilat āyātuhū ā'jamiyyun wa'arabiyyun qul huwa lilladhīna āmanū hudan washifā'un walladhīna lā yu'minūna fī ādhānihim waqrun wahuwa 'alayhim 'aman ulā'ika yunādawna mim makāni ba'īd

And if We had made it a foreign [i.e., non-Arabic] Qur’ān, they would have said, "Why are its verses not explained in detail [in our language]? Is it a foreign [recitation] and an Arab [messenger]?" Say, "It is, for those who believe, a guidance and cure." And those who do not believe - in their ears is deafness, and it is upon them blindness. Those are being called from a distant place.¹³⁹⁸