Right, God doesn't need anything. But God has done it anyway. Who am I to question the acts of God?
Okay, so you seem to be under the impression that if you still your mind you will then feel/"hear" what God wants. So when Christopher Lee McCuin decided to become a murderer and kill a 21-year-old and then eat her body, that was actually God working through him. Because after all, he stilled his mind too, and God told him to do this.
If we can be decieved by other humans, why couldn't we be decieved by other beings? How do we know if what we think is god in our heads, is actually god? what sort of truth do we compare it to?
I think the creator of the universe doesn't need a book to talk to people. Just still your mind.
You may enjoy reading this
https://www.cia.gov/readingroom/docs/CIA-RDP96-00788R001700210016-5.pdf
Your questions are valid. Ultimately you have to trust yourself, your own intuition. I'd rather trust myself than a book.