Deuteronomy 4:12

12 Then the LORD spoke to you out of the fire. You heard the sound of words but saw no form; there was only a voice.

Read Deuteronomy 4:12 Using Other Translations

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.
Then the LORD spoke to you out of the midst of the fire. You heard the sound of words, but saw no form; there was only a voice.
And the LORD spoke to you from the heart of the fire. You heard the sound of his words but didn’t see his form; there was only a voice.