This reminds me of a Cal DeWitt story. He & a number of reformed
theologians took a few years to determine a definitive reformed position on
the question of origens.
At the end, he raised the question, "when we stand before the judgement seat
of Christ, will God question us on whether we determined correctly the
origens and age of the earth?"
The consensus was no, that God is not particuliarly concerned (or impressed)
with our knowledge.
"Then what will God ask about our relationship to creation?"
"He will judge us on what we did with it, not how old we thought it was."
The point is is that the Bible (and it's author :-) ) is much more
concerned with what we do and how we act, than what we know. To a large
degree, the age of the earth is irrelevant to the living our daily lives.
On the other hand, creation stewardship does affect everyday life.