i.e. No resemblance or representation of God, whereby either his essence or properties or actions were represented, such as were usual among the heathens.
Related Commentaries of Deuteronomy 4:12
Deuteronomy 4:12
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; onlyb ye heard a voice.