Deuteronomy 4:12
And the LORD spake unto you out of the midst of the fire: ye heard the voice of the words, but saw no similitude; only ye heard a voice.
And the Lord spake unto you out of the midst of the fire,.... For the Lord descended on Mount Sinai in a cloud, in fire, and was in the thick darkness, from whence he delivered out the ten commands:
ye heard the voice of the words; distinctly and plainly, not only the sound of them, but the words themselves, and so as to understand what was meant by them;
but saw no similitude; not any likeness of the person speaking, by which they could form any idea of him in their minds, which was purposely done to prevent idolatry:
only ye heard a voice; that was all.