Doom, Demons, and Heaven
It's not my intention that this post be read as antagonistic towards anyone (especially not Dark Virtue and TJguitarz, both of whom I believe to be essential members of this forum. That being said, my comments below are fairly strong comments and will come across as such.
@ DV (and as collateral, everyone else) :
Funny, the definition of demon found on dictionary.com seems to be much more like follows:
1. an evil spirit; devil or fiend.
2. an evil passion or influence.
3. a person considered extremely wicked, evil, or cruel.
4. a person with great energy, drive, etc.: He's a demon for work.
5. a person, esp. a child, who is very mischievous: His younger son is a real little demon.
6. daemon.
7. Australian Slang. a policeman, esp. a detective.
Webster's Dictionary puts it this way:
Etymology:
Middle English demon, from Late Latin & Latin; Late Latin daemon evil spirit, from Latin, divinity, spirit, from Greek daimōn, probably from daiesthai to distribute — more at tide
Date:
13th century
1 a: an evil spirit
b: a source or agent of evil, harm, distress, or ruin
2 usually daemon : an attendant power or spirit : genius
3 usually daemon : a supernatural being of Greek mythology intermediate between gods and men
4: one that has exceptional enthusiasm, drive, or effectiveness <a demon for work>
I find it kind of amusing that you chose the one definition of "demon" that is purely naturalistic and sounds most like a simple human being. And, I should add, that is very removed from the definition found in Doom III. The definition of demon as a spiritual being of evil or a force of distress and harm is a very old and widespread tradition, not only amongst Christians -- although I know with the many cultural definitions come unique differences.
Now, as to demons in Doom III and whether you kill them "for Jesus." I haven't played Doom III, so I have to rely on my knowledge of Doom I and Doom II and the wikipedia synopsis. However, at the beginning I'd like to put out a definition of demons that I believe lines up with the Bible: Demons are spiritual beings or forces that are out of line with or opposed to the will of God.
Does this describe the demons in Doom III? I'm not sure. I will point out, however, that if chainsaws, grenade launchers, and everyone's favorite Big F Gun are effective ways of defeating them, that sounds to me that they're much more physical than spiritual. Also, they seem to run Hell, something that doesn't occur in the Bible (the "Lake of Fire" that inspires our concept of Hell is a final destination/punishment for demons, not their home base.) So, it seems to me that, like in Hellgate:London or World of Warcraft, these "demons" are functionally/structurally
polemically evil aliens or monsters.
Jesus is not mentioned in wikipedia's synopsis of Doom III. So it's pretty hard to say that you're killing said polemically evil aliens or monsters for him.
Would Jesus toss you a BFG to help you kill demons? No. He'd deal with them himself. He's not a pansy that needs us to deal with demons because he can't. When the disciples in the Bible cast out demons, they do it in his name (aka, he does it for them.) When demons in the bible run into him, they're scared out of their... minds? whatevers. In the end, the Bible shows that Jesus triumphs over demons. He doesn't need guns to do it. Not to mention that seeing as demons are spiritual beings, the BFG wouldn't make a difference, unless you're arguing that BFG stands for "Big Faith Gun" --- and then I'd be arguing that it's a corny idea based on very very bad theology.
As to Heaven being mentioned or detailed in the Bible: yes, yes it is... but not to the extent of "Heaven the Game." It's mentioned by Paul in 2 Cor 12:2. It's talked about and even described in the Revelation, but so is the New Jerusalem (in much more detail.)
That being said, many Christians love to expound on and extend what's in scripture. Is this bad? Maybe not, but it's not quite the same thing.
The Heaven that Christians aspire to is alluded to here: John 14:2-3, where Jesus says that he is going back to the domain of his father (God) to prepare a place for his followers. We define Heaven as that domain.
References to heaven exist all over the Bible: the book of Job, the story of Elijah, Paul's letters, the letter to the Hebrews, and of course the Psalms and the references to the beliefs of the Israelites and even beforehand that God was the "maker of Heaven and Earth."