The Myth of the Given F/A-F

A position required for Christianity, Islam, and many other religions is Foundationalism. I'll start with a definition of Foundationalism straight out of my correspondence with one of my professors: [Foundationalist says] so there needs to be some
substrate upon which all reasons rest (lest there be an infinite regress). Sellars [Anti-Foundationalist]
denies the call for an "ultimate substrate" of justification (that would be the
Given,...

For a much sexier explaination check this out: SEP Article on Foundationalism/

The Ultimate Substrate of Justification seems like an appropriate label for any of the almighty God(s) out there.

So here's the deal:

Let's hash out Foundationalism and Anti-Foundationalism.

To be fair, science might also be construed as a Foundation, as could anything else, really. The Foundationalists come first historically, and thus I eagerly await the start of this discussion.

I re-read my post and feared I'd become guilty of baiting, as I didn't write a clear question:

How do you (person x) argue for your particular Foundation, whether it be Allah or Jesus or whoever?