قُلْ أُوحِىَ إِلَىَّ أَنَّهُ ٱسْتَمَعَ نَفَرٌ مِّنَ ٱلْجِنِّ فَقَالُوٓا۟ إِنَّا سَمِعْنَا قُرْءَانًا عَجَبًا
Qul oohiya ilaiya annna hustama'a nafarum minal jinnni faqaalooo innaa sami'naa quraanan 'ajabaa
Say [Prophet], ‘It has been revealed to me that a group of jinn once listened in and said, “We have heard a wondrous Quran,
Say: it has been revealed to me that a group of the jinn listened in and said, 'We have heard a wondrous recitation
The Prophet learns of this audience by revelation, without having seen it: the verse is the report reaching him, and the whole surah after it is quoted speech he is told to pass on. Nafar names a small band, classically somewhere between three and ten, and the verb for their listening is the deliberate form, attention paid on purpose.