He's a New Yorker born and bred (and there is a passage talking about that on the site's Spidey page), but I think that it's cultural osmosis mixed with some ancestry from his late parents, and with May's Protestant background, skewing him towards that Protestant-Lite view of God makes sense. Still, I think he's fairly abstract in his beliefs, relying more on Science! to be his pillar of faith (and humanism).