Be specific. Which word or phrase in my post "brings up an archaic meaning" or "elides" [sic] that meaning to a modern discussion on the subject? Because I'm not aware of doing any such thing and have the distinct feeling that the supposed difference between "modern" and "archaic" definitions of "faith" are all in your head.
I was specific, but I'll be specific-er.
Reason and religion have been at loggerheads since the publication of Origin of the Species. The late Renaissance early Enlightenment thinkers such as Descartes and Kant believed that a person could construct a fully logical argument to demonstrate religious truths, particularly the existence of the Christian god. However, during the 19th century, that was turned on it's head -- the truths of natural philosophy were doing things like proving the world was much, much older than six thousand years, discovering all kinds of mechanistic explanations for what had hitherto been considered divine phenomenon (such as the weather). Worse, the idea of a well-ordered universe just seemed to be wrong -- it was a cosmos filled with a great many . . . just perplexing things. Origin of the Species was the final nail in the coffin, though. By saying no divine intervention was required for the creation of humans, evolutionary theory created a schism between "reason" and "faith" that exists to this day.
So, while it was reasonably for a person like Rene Descartes to both reasonably and religious, since then there's been a lot of change in the relationship between secular and religious knowledge.
By saying, "Just look back at the history of reason" to demonstrate some identity between reason and faith ignores the weather change in reason and faith dating from the late 19th century (though certainly present to a lesser extent quite a bit before that; I'd say the real break between faith and reason, in the west, was burning Bruno at the stake -- Bruno's reason went head to head with religious faith and they set him on fire for daring to challenge religious faith). So, by appealing to archaic definitions between reason and religious faith to say that, today, there continues to be an identity between them is a trick. It's a trick that depends on a person being ignorant of the ways religious faith and secular reason have almost completely parted ways.
Since the middle to late 19th century, secular reasoning (not just in science, but in law, politics, economics, you name it) has been at considerable odds with religious faith. Sure, if you look back at the history of both you can find a time where that's not true, but it's true today. Appealing selectively to the past to "prove" something, while ignoring incredibly significant and relevant historical events that occurred along the way, is rhetorical trickery.