Ash-Shura - 42:51

وَمَا كَانَ لِبَشَرٍ أَن يُكَلِّمَهُ اللَّهُ إِلَّا وَحْيًا أَوْ مِن وَرَاء حِجَابٍ أَوْ يُرْسِلَ رَسُولًا فَيُوحِيَ بِإِذْنِهِ مَا يَشَاء إِنَّهُ عَلِيٌّ حَكِيمٌ
[42:51]
And it is not for any mortal that Allah should speak to them, they could not bear to hear and they did not see.
It is not fitting for a man that Allah should speak to him except by inspiration, or from behind a veil, or by the sending of a messenger to reveal, with Allah's permission, what Allah wills: for He is Most High, Most Wise.
And it was not (vouchsafed) to any mortal that Allah should speak to him unless (it be) by revelation or from behind a veil, or (that) He sendeth a messenger to reveal what He will by His leave. Lo! He is Exalted, Wise.