communication between God and mankind

وَلَوْ جَعَلْنَـٰهُ مَلَكًا لَّجَعَلْنَـٰهُ رَجُلًا وَلَلَبَسْنَا عَلَيْهِم مَّا يَلْبِسُونَ

And if We had made him [i.e., the messenger] an angel, We would have made him [appear as] a man, and We would have covered them with that in which they cover themselves [i.e., confusion and doubt].