And it is not (possible) for a man that Allah should speak to him except (through inspirational) communication or from behind a veil or by sending a messenger who communicates by His permission what He wills, He is certainly High, Wise.
Three ways of communicating Divine messages are described. Before receiving the Quran Prophet Muhammed (PBH) did not know what the book was and what belief was, he was guided through the Quran, then he became the source of guidance for others towards the path of Allah (SWT) the Owner of everything.