What's this!? Something I completely overlooked!?

This brings up a question. If what you're saying is true, Summoner of Leviathan, if Yevon's religion didn't exist before Sin, then how could there be Fayth (a minimal amount maybe) around for the Summoners to use if it was Yevon who suggested the Fayth? Also, if the Fayth were what they (the Summoners) needed to kill Sin by giving their souls (or rather Aeons), then what did the Summoners summon exactly if their were no Fayths around. Wouldn't that corroborate my thought that Yevon (as a religion) has been around even before Sin?

Even if you don't agree, it makes a good theory, no?