﴿ فَقَرَأَهُۥ عَلَيْهِم مَّا كَانُوا۟ بِهِۦ مُؤْمِنِينَ ﴾

“and had he recited it unto them [in his own tongue], they would not have believed in it.”

and had he recited it to them that is to the disbelievers of Mecca they would not have believed in it disdaining to follow it.