Those voices are you speaking to you - the voices you hear are 'parts' / 'expressions' of you, you haven't accepted as you as one with you. Thus - you experience it as 'voices' separate from you - because the voices represents expressions of you that exist within you that you have separated yourself from. Thus - when you 'hear' such statements of voices again - observe your experience of the voice - if it's 'stern' for instance - where have you not accepted yourself as being 'stern' / self disciplined with yourself within and as your dedication and commitment to you as life within and as oneness and equality. If the voice is comforting - where are you too hard on yourself and not allowing yourself to be gentle with you. Then you make statements: I am gentleness, I am comfort, I am disciplined, I am committed to me, I am dedication etc. Then forgive yourself that you have allowed yourself to separate you from yourself and accept yourself as dedicated, committed and gentle.
Veno