This quest to determine which religion is true sounds a lot like the genesis story of Mormonism. Joseph Smith, its founder, was deeply concerned about which religion had the truth. He prayed to know which religion to join. God the Father and Jesus Christ supposedly appeared to him and told him that none were true, but that he was chosen to restore the true religion.
I worry a lot about the danger of accepting that there are unassailable moral truths established by a supreme being. I’m a former Mormon, and the catalyst for my departure from the religion was my profound disagreement with its anti-LGBT teachings. I was taught to follow these teachings even though they seemed wrong to me because they came from God, and things that come from God are always good, whether we like them or not.
If we are to live like theists and accept that there are objective moral truths that exist because a supreme being said so, aren’t we in danger of deceiving ourselves and causing undo harm?