I don't think theism implies closure. I think it's reasonable to alter our perspective of theistic concepts as we learn more about the universe. But fundamentally, theism isn't so much concerned with "how". It's concerned with "why".
Science is a self-checking process that demands testable evidence. This is why science is just so damn good at ascertaining "how."
What is the criteria by which theism ascertains "why?" By what process do we dicipher the false claims from the factful?