what is the ultimate purpose of our lives if we just disappear?
None. My life has no purpose to the universe. It only matters to me and some finite number of other animals both human and otherwise. That is much of the power of humanism. It's about life and making the most out of it for as many sentient creatures as possible, equipping each to with the resources and opportunities to determine their own purpose.
And be careful not to commit this fallacy:
"Appeal to consequences is an argument that concludes a hypothesis (typically a belief) to be either true or false based on whether the premise leads to desirable or undesirable consequences. This is based on an appeal to emotion and is a type of informal fallacy, since the desirability of a premise's consequence does not make the premise true."
we don't know what eternity will bring really.
Yet you say that if it is eternal unconsciousness, that life had no meaning.
Scientism is a belief that attributes too much to science than it is capable of doing.
I disagree. Scientism is a pejorative word (the commonest usage) demeaning the unwillingness to believe by faith, much like materialism. Theism is a belief that attributes too much efficacy to faith-based thought, which is always sterile, as creationism is compared to evolutionary science and astrology to astronomy.
It's a common mistake of theists to think that science is trying to answer theistic (metaphysical) questions, and just isn't quite up to the task for a lack of the proper tools, which religion provides while scientists continue in vain trying to answer metaphysical questions with nothing but laboratories and observatories. That's a misunderstanding of what science does and what can be known. Metaphysical statements are neither correct nor incorrect. They're "not even wrong." They're undecidable.
Correct and incorrect statements are falsifiable claims, incorrect ones being those that are falsifiable and have been falsified, with correct ones being those that are falsifiable but won't be falsified (rebutted with evidence) because they are correct. These are the issues theology deals with, but as I said earlier, such pursuits are uniformly sterile, theology being studies based in a god belief. No argument that begins with the premise that a god exists can produce a sound conclusion, or any idea that can be used to describe and predict nature.
The evidence does not need to be empirical. I'm not sure how it could be.
It can't not be empirical if it is evidence.
It's true that if the gospel writing is evidence, so is records in every scripture ever.
Yes, it is evidence, because it is evident to the senses. But evidence of what? What sound conclusions can be derived from apprehending scripture through one's eyes or ears (or fingers if deaf and blind). What I conclude is that it contains thoughts that human beings once put down on paper, people who may or may not have believed them, and shared with others who believed it, ideas that might be correct (David was an ancient king of the Hebrews), incorrect (woman was made from a rib), or "not even wrong" (Jesus sits at the right hand of God in heaven).
Scripture is not evidence of a deity. To do that, it would need to contain passages that human beings simply couldn't have written, and even then, naturalistic explanations involving extraterrestrials are more likely than gods as authors, but both become more likely if we find such a revelation. Likewise with uncovering a falsifying find upending evolution such as the irreducible complexity in biological systems that the ID were in search of. Suddenly, only deceptive intelligent designers remain to explain that, but naturalistic hypotheses remain preferred according to Occam's principle of parsimony.
Inner inconsistencies [of the Bible] have been mainly answered.
But not satisfactorily. The Bible contains internal contradictions, moral and intellectual errors attributed to a tri-omni deity, and errors of science and history.
So science can never say that there is no God or supernatural.
That's unimportant. It can also not say that there are n vampires or leprechauns, but that isn't slowing it down any.
We can rule out some gods, but not all. Neither the deist god nor any other non-interventionalist god can be ruled out, intervention being coming to earth, performing miracles, answering prayer, or leaving revelation - doing something empirically discernible.
Interventionalist gods said to have done things that we know didn't happen CAN be ruled out. Did you notice when I referred to falsifying evolution, an honest god was not one of the remaining possibilities. That's already been ruled out by the evidence that currently supports the theory. If evolution didn't occur as it appears to have occurred, then it was a massive deception perpetrated by a deceptive superhuman intelligence of great power - maybe Loki or Shiva, but not Jesus.
That's an empirical disproof - based in evidence. We can also rule out gods described in mutually exclusive terms as we do married bachelors, a disproof using pure reason. So, for example, imagine a god said to be perfect, but also said to have made errors that it regretted and attempted to correct. You can see that no such is possible any more than a married bachelor is, and for the same reason.
So the supernatural can exist and science know nothing about it and cannot study it and call it natural.
Supernatural is an incoherent concept like married bachelor. What is proposed is a realm capable of modifying nature but being undetectable even in principle. Bothof those things cannot be true about the same domain. Reality, existence, and nature are all the same thing. To exist is to be found in space and time interacting with other things existing. All of these thing are real, and the collection of them is reality. Another name for the collection of existents (things that exist) is nature. Everything that exists is another aspect of nature, and is detectible with the right sensory apparatus in the right place at the right time. To posit a realm, to call it real, and to say that it isn't detectible even in principle and not a part of nature is to propose a married bachelor.