Al-A'raf 7:184

Awa lam yatafakkaroo ma bisahibihimmin jinnatin in huwa illa natheerun mubeen

Then do they not give thought? There is in their companion [i.e., Muḥammad (ﷺ)] no madness. He is not but a clear warner.

Have they not reflected that their fellow (i.e. the Holy Prophet) does not suffer from any madness? He is but a plain warner.