well, the "voices" I hear are definitely NOT God
Many times, the "Voice" is their subconscious or alter ego that surfaces due to lack of control, either by chemical imbalances or other stresses. However, in the NOR, not everything is concerned with our best interests; they have their own agendas - both good and bad. As a result, the energies (or voices or "God") can influence our behaviors. And it can be very difficult for an unstable mind to tell the difference.
It's not so difficult as you think:
try sitting in a swivel chair and spin about at least 40 times. Then try to stand straight up... but which way is up? You cannot, because you have become unstable.
Although this is a very simplistic example, it shows just how when the mind is unstable, even simple discernment is gone.