وَلَوْ جَعَلْنَـٰهُ قُرْءَانًا أَعْجَمِيًّا لَّقَالُوا۟ لَوْلَا فُصِّلَتْ ءَايَـٰتُهُۥٓ ۖ ءَا۬عْجَمِىٌّ وَعَرَبِىٌّ ۗ قُلْ هُوَ لِلَّذِينَ ءَامَنُوا۟ هُدًى وَشِفَآءٌ ۖ وَٱلَّذِينَ لَا يُؤْمِنُونَ فِىٓ ءَاذَانِهِمْ وَقْرٌ وَهُوَ عَلَيْهِمْ عَمًى ۚ أُو۟لَـٰٓئِكَ يُنَادَوْنَ مِن مَّكَانٍۭ بَعِيدٍ
Wa law ja'alnaahu Qur-aanan A'jamiyyal laqaaloo law laa fussilat Aayaatuhoo 'a A'jamiyyunw wa 'Arabiyy; qul huwa lillazeena aamanoo hudanw wa shifaaa'unw wallazeena la yu'minoona feee aazaanihim waqrunw wa huwa 'alaihim 'amaa; ulaaa'ika yunaadawna mim maakaanim ba'eed
If We had made it a foreign Quran, they would have said, ‘If only its verses were clear! What? Foreign speech to an Arab?’ Say, ‘It is guidance and healing for those who have faith, but the ears of the disbelievers are heavy, they are blind to it, it is as if they are being called from a distant place.’
Had we made it a Qur'an in a foreign tongue, they would have said, 'If only its verses were made clear! A foreign tongue and an Arab speaker?' Say: for those who believe, it is guidance and healing; but those who do not believe — in their ears is a deafness, and it is blindness upon them. They are being called from a faraway place.
The same recitation is guidance and healing for one listener and a weight in the ears of another, which places the difference in the hearer. The objection gets answered by imagining its opposite: a Qur'an in a foreign tongue would have drawn the complaint just as fast, so language was never really the issue. The closing image has them being shouted to across a great distance, where the voice arrives and the sense does not.