Surah Fussilat, ayah 26

41:26

وَقَالَ ٱلَّذِينَ كَفَرُواْ لَا تَسۡمَعُواْ لِهَٰذَا ٱلۡقُرۡءَانِ وَٱلۡغَوۡاْ فِيهِ لَعَلَّكُمۡ تَغۡلِبُونَ ٢٦

Waqālal-ladhīna kafarū lā tasma'ū lihādhal-qur'āni wal-ghaw fīhi la'allakum taghlibūn

And those who disbelieve say, "Do not listen to this Qur’ān and speak noisily1391 during [the recitation of] it that perhaps you will overcome."

Footnotes

1391 Other meanings include "speak improperly" and/or "make a clamor." The purpose of this was to prevent the hearing or understanding of the Qur’ān.