وَيَقُولُ ٱلَّذِينَ كَفَرُواْ لَسۡتَ مُرۡسَلٗاۚ قُلۡ كَفَىٰ بِٱللَّهِ شَهِيدَۢا بَيۡنِي وَبَيۡنَكُمۡ وَمَنۡ عِندَهُۥ عِلۡمُ ٱلۡكِتَٰبِ ٤٣
And those who have disbelieved say, "You are not a messenger." Say, [O Muḥammad], "Sufficient is Allāh as Witness between me and you, and [the witness of] whoever has knowledge of the Scripture."1
Translation: Saheeh International (English)
1 i.e., those who recognize the truth through their knowledge of previous scriptures.
Each word's meaning and sound
Those who disbelieved in Allah say: You, O Muhammad, have not been sent by Allah. Tell them, O Messenger, Allah is sufficient as a witness between me and you to the fact that I have been sent from my Lord to you, as well as those who have knowledge of the heavenly scriptures that contain my description. The one for whom Allah is a witness to His truthfulness, is not harmed by the rejection of those who deny him.
Al-Mukhtasar in interpreting the Noble Quran