From A New Hope's transcript:
LUKE: (sighing) Oh, God, my uncle. How am I ever going to explain this?
This is most-likely a form of Early Installment Weirdness (Warning, yadda yadda) given that as far as I know, none of the other films ever mention a "Capital G-God," either religiously or through slang and either the Force or various minor gods are generally believed in.
Similarly, "Hell" was mentioned a few times in the films. Eventually, it was explained that Hell was another name for Chaos, so I'm wondering if a similar retcon was ever made to explain this.
My question is, did the EU ever explain which God Luke was referencing?