There is absolutely no reason to believe that one’s inner voice has anything to do with truth from God.
Yes there is. Especially when you listen to it and it opens you to the Divine. When that happens, it becomes perfectly clear what is meant by, "Thy will, not mine be done". So yes, it does have to do with the Truth of God.
Just because people believe that does not make it a reality.
Actually.... that's not true. Believing it does make it become Reality. You darn tootin it does.
Why? Because faith, hope, intention, divine Will, and surrender to that image, does in fact open you to it, and it becomes your lived Reality.
People can imagine any number of things.
Yes indeed! People imagine they are separated from God, unworthy, unlovable, unloved, etc. And that becomes their lived reality to them. What we imagine can either damn us, or save us.
Such a voice is only valuable to the person who experiences it and believes it came from God. But just how valuable is it if it did not really come from God?
If the result is you live as God would in this world, it's value is Eternal. All else fades away, but not that.
According to my beliefs, truth from God can only be found “out there” because God does not communicate directly to anyone except His Messengers who reveal the religious scriptures.
And this is specifically why I feel it is unhelpful to the spiritual aspirant on their path to Union with the Divine. It's great for teaching the basic principles by objectifying them. But unless it becomes internalized and a lived, experiential reality, one which produces natural fruit from the Vine that is alive and living within you, it becomes just a dead end religion to you. A finger pointing at the moon, is not the Moon. You have to step beyond the finger into the Light of what it is pointing to.
Scriptures do not have to be inerrant in order to convey God’s truth. They only have to come from a real Messenger of God, as opposed to someone who just believed they heard from God.
Anything which speaks the Truth of God is a true Messenger, including that songbird who quoted Holy Scripture to me tonight in the park. All are Divine manifestations, if you have the ears to hear, the eyes to see, and the soul to receive.
In my opinion, the problem with mysticism is that once a mystic decides that they have a direct line to God, they think they no longer need any scriptures as a source of truth, so they miss out on God’s truth as it comes through scriptures.
Well that's not true at all! The Truth of God shines wherever it is heard. Scripture sings anew with the Light of the Divine Mind when you are opened to it. By contrast, previously that had the sound of a scratchy record by comparison. They aren't done away with, they at last make sense!
They also become an island onto themselves disconnected from the rest of humanity.
100% completely a wrong understanding. Absolutely the opposite is true. Without it, we are all disconnected from not only the rest of humanity, but ourselves as well as disconnected from God. To connect with God, connects you as God with the whole of creation. It opens you to the world. It opens you to yourself. It opens you to others.
This might make them feel superior and special but it does not help anyone else in society.
The absolute is opposite is in fact the reality of it. This is just speculation on your part, and perhaps some resentment in there? On the contrary, it makes you feel the servant of others, not superior. It makes you realize how nothing your own ego is in the Light of God. It lets you at last "love others as yourself".
It does not engender any sense of community or working together for a common goal. The entire focus is on the individual and their connection to God.
While the path of the mystic is a largely solitary one, that is in a true sense by design. You die alone, you know. You have to die before God, in order to enter God. But one that is done, then you rise from the grave that was your life in your ego-self, and the whole world is your focus. You see as God sees. Your compassion is God's compassion. Your grace is God's Grace. You become God in the world through your body as vessel.
This is a good thing. Put on your oxygen mask first, if you hope to help others on with theirs. That's an act of love, not selfishness.
This can never work for all of humanity so I do not see the value in it as compared to the revealed religions, which have been the cause of the advancement of civilizations throughout human history.
While religions may have civilizing influence, with both good and not so good results, the path to God is again, a solitary one. But without that, a religion without the Living Soul breathing through its members, is not in fact drawing from Living Waters, but instead from a bucket of water someone had handed down to them, not refreshed since it was drawn hundreds or thousands of years in the past. God's Truth, is not static. If it's not your truth from within you, it's not your Truth.