Chesterton certainly played a role, but it was mostly the posts on Aron's blog themselves. The story is like this: I was born into a christian family, but like many young people, and helped by some written works, some healthy amount skepticism, other not-so-healthy things, and what I saw inside and outside my social circles, I came to doubt my previous beliefs.
Anyway, then I discovered Aron's blog, and it was like a new world open to me. Something that I've experienced very few times in my life; maybe when I found SICP/Lisp…
And it could even ve said that I discovered that blog thanks to SICP since it went something like this: OCW > SICP > Paul Graham > Hacker News > (eventually) The Blog. ^^
Scott does write from an atheist viewpoint, since he is atheist, but even though I am not, I still enjoy his writing very much, just as I've liked many of PG's essays or LessWrong articles. It is not necessary to hold the same beliefs to enjoy intellectual fellowship/communion as it is (usually) exemplified by Hacker News itself.
Also, if you want to, I can share with you some of my favorite articles there. I have a huge list though.