أَمْ لَمْ يُنَبَّأْ بِمَا فِي صُحُفِ مُوسَىٰ
“Or has he not been informed of what was in the scriptures of Moses”
This ayah is part of Surah al-Najm, which the Prophet ﷺ recited in full at this event -- building to the prostration verse (53:62) that moved even the Quraysh to fall into sajdah with the Muslims.