It's on my end but I can't get the audio to work right now, but is he saying that like a figure of speech as in "i hear his voice in his words' or is he saying it that he's literally listening to an outside voice?
One of my last few best lifelong friends has suffered with depression since high school and now would and has been diagnosed with a few mental problems that I can't spell right now. He's highly religious and Jewish. But he believes in codes of the book and other things I don't understand. He hears God or Jowah or who ever he says it is. It incredibly sad and he was tested as a high IQ too.
I sometimes wonder about the old adage that very high intelligence sometimes shares space with insanity. Whatever the present parameters of what insanity is.