I'm currently running a 3-year long campaign that is coming to an ending in which God is likely to appear as an NPC. Since this is the end of the campaign I won't need to manage it for very long, but I will almost certainly have to run direct dialogue with God or portray God in ways that touch on important or sensitive eschatological issues.
This game takes place in a post-post-apocalyptic (not the Biblical apocalypse) setting, approximately three hundred years in the future. The PCs started in the mega-city of Kansas, which is a state in the United States of America. The game essentially takes place 'in the real world', though there are a number of obvious differences, like the existence of flying cars, much more advanced natural-language processing, the proliferation of fusion-based technology, etc.
Obviously this in-game God is necessarily a fictionalized representation of real-world God, but we're all fellow Christians and I'm concerned about my in-game choices for or about God transgressing our real-life boundaries as believers. I want to do this is a respectful and sacred way, and I am worried about being up to the task.
How can I respectfully handle introducing the sensitive subject of God to my game? Or should I just flat-out not do it?
I hope it goes without saying that answers from experience are far, far better answers than uninformed speculation. I haven't explained all of the relevant theology and eschatology, because answers should be bringing Good Subjective experience to the table. I also hope it's obvious that answers (or comments) which are insensitive or hostile to religious concerns, on a question about how to be sensitive to religious concerns, are inappropriate.
(Further recommended reading is Meta.Christianity's post about answering as a religious person and Meta.Islam's post about avoiding theological debates, apologetics, or other discussion masquerading as a question/answer/comment; and, of course, Be Nice.)