Okay, something simple. The grammatical status of the words "the truth". Those words means that there is one version of the truth. So there can't be different versions of the truth. That is simple to test: 2 examples are given now.
Someone: The truth of how the world is...
Me: Stop, you don't have to continue, because I can just do that differently and think differently about the truth than you. I.e. as long as humans can't in practice eliminate subjectivity, I just have to do something different than you and out the window goes the truth as only one truth for the world.
Someone: The one true God is...
Me: Stop, you don't have to continue, because I can just do that differently and believe differently about God than you. I.e. as long as humans can't in practice eliminate subjectivity, I just have to do something different than you and out the window goes the one true God.
Yeah, it is that simple. In practice both science and religion are limited as it comes to the truth. I know, how to test for it, because I accept for the subjective subjective results as valid evidence. For the objective I accept objective evidence as valid, but I try not to confuse the 2.
That is how I learned to do it and I accept that you can do subjectivity and objectivity differently, but I will still just check if what you do appears to be subjective regardless of you claim science or religion, how ever you do it.
Regards
Mikkel