Whatever your beliefs in the case of a Omnipotent god or goddess if they really wanted people to follow there teachings y not have an immortal messenger instead of profits that just write down everything?
And if there was an immortal messenger would you take what he/she said seriously or just ignore it?
In all honesty, in this day and age how many people do you know WOULD believe if there were an immortal messenger or even a mortal messenger?
More than likely that person would end up locked up somewhere and labeled as a lunatic for hearing the voice of the Divine.
The basis of most religions is faith, faith in the teachings, faith in that if you cooperate with All That Is you will benefit in some way, and faith that your prayers will be answered. I don't need a messenger coming down and tapping me on the head, my Goddess does that aplenty all on Her own lol