The more examples of such idiocy I see, the more I think that Warhammer 40.000's Imperial religion (the belief in the Immortal Emperor) is a parody on Christian religion.
No offense against the Christians, I just hate those hypocrites who claim they believe in God and stuff, but their behaviour is far away from what it should be.
BTW I'm an Atheist.

Yeah, I've had teachers approach me and tell me everything I like is 'Satanic". I love being the bearer of bad news guys (Guys being the teachers.), but I am not a Satanist.
1) I listen to metal, not black metal. Look it up you dumb asses.
2) My views are my views, I am not a Christian, get the fuck over it. Deism is similar to it!
3) I take great pride knowing I scare you. Seriously, it makes me giddy.
And yes, hypocrites are a pain. For example, I once knew a man who was a pastor from Lithuania. He preached on and on about how the Lord is the Almighty and if you sin you go to 'Hell', yet he abused his kin and preached ignorant, harmful propaganda.
Come to think of it, religion is just propaganda...

I looked up that word and have no fuckin idea what you were saying...on plus side, just got Half Life 1 anthology and Half Life 2 for $11.88!!!! WOOT!!!

I'll stay out of this. I'm a very opinionated Atheist and if there's one thing I can't stand - it's Evangelists. Especially ones who haven't read the Bible properly. This video is a prime example of that.
One of the points of Warhammer is that it's looking quite satirically at modern Christianity and seeing what it can turn into. If you read the Horus Heresy books you can see that point made quite clear - in the the 30th milennium the idea was not to praise the Emperor but as time went on they became fanatics, drawing from Christian ideals and small sects who decided to praise him as a god. The other thing to note is that the 41st milennium people have "lost" science, and treat machines as holy gifts. This is another Christian thing, the idea that people who don't understand something will just say "Ah, god did it."

That's what the preacher said when he raped his choir boys... >=)

I didn't read the books (shame on me), but I know that the worshipping of the Emperor started after putting him on the golden throne due to wounds he suffered from fight against warmarshal Horus.
But yes, you said it better, it is a satire. The Holy Inquisition, the fact you either worship the Emperor or are a heretic (therefore you will be probably shot or burned), that is what Christians did.
It is ironic that the religion telling you to be good man did cause so much bad things, isn't it? But that is for another debate.

I've always thought that in order to convert someone you need to make him doubt first. It's hard to convert another believer unless his beliefs are put into question. The spanish converted the american indians after they were defeated (with better weapons and technology, not with better gods) so once a person starts questioning his beliefs, it's easier to put your belief in front of him as the truth.
I also think we humans are genetically wired to believe in something greater than ourselves, maybe because we're social creatures and believing in a god makes you feel like you have company even when alone. Every single society has a religion at some point in their existence, so it's most likely a human or genetic quality that urges us to believe. We are also intelligent and constantly question our surroundings, so whenever we don't know an answer to something, we make it up, sometimes involving our gods into the process.
If god was an omnipotent being that somehow has shown interest in this tiny speck of a world in the middle of the infinite cosmos, it's kind of odd that he programmed us to have beliefs but they always end up being completely different beliefs from region to region. The fact that we believe is not proof of his existence. The fact that we don't is not proof of his non-existence either.
Just wanted to throw this into the pile. I haven't even seen the video. People who are too locked into their beliefs without a shred of evidence make me sad and I'm just starting my day.

Well religion DOES teach you to be a good person, and you're SUPPOSED to be. But it's just that in the entire history of the WORLD there has never been a SINGLE Christian because they simply don't know how to follow the rules. A lot of my Muslim friends are doing it now too.
Christians (at least all the ones I know, and all the televangelists and whatnot) are bigger Atheists than me because they all pretty much outright defy the bible. The bible isn't a set of GUIDELINES, it's a book of RULES. You're supposed to follow those rules no matter what, making no compromises or excuses. Saying "god did it" is simply not acceptable.
Back to the Emperor: Smaller sects during the Emperor's Crusade had already begun worshipping him, and it was highly illegal at the time, these people would be punished and the Emperor personally said that it's simply not what he wanted. I think this probably alludes back to Jesus, he wasn't really "revered" until after his death.
As to when it was generally acceptible to worship the Emperor, I'm not sure. But you probably have it right, it was probably the religious sects who put him there in the first place.
Even the story of the Emperor and Horus alludes to the bible - Horus is like Lucifer, god's favourite son who decides he's better than the Emperor.

It's not exactly easy to follow these rules either, because they keep contradicting them selves. One place it says specifically what you should eat, wear and how you should behave, while in another it says that you shouldn't even care about it (the non-care part is somewhere in Ezekiel, can't remember where the first part is in). Maybe not the best example of this, but you'll find many similar contradictions here and there.
So such as it is, with all the different interpretations, that no one can agree on, it's more like a pick-and-choose book for your own branch of Christianity.
I've personally taken the apathetic atheist approach and is standing on the sideline, watching with a mix of hilarity and dread.

Maybe they were really trying to write one of those choose your own adventure books but someone forgot to add the "turn to page ##" to the end of each scene.

That's because the bible even comes from the word "bibliography", it's a collection of books that's been written over time. When one dude thinks another apostle or something got it wrong, he just makes up something to make it easier for himself.

Quick moment of fact-iness. You're wrong. Completely wrong. Horus = Egyptian God. Read Budge. The Warhammer thing is based on Pharonic theocracy, not Christianity. You don't even need a basic knowledge of Egypt to ascertain that, just an afternoon spent watching Stargate.

Uhhh, I don't think you quite understood. In Warhammer 40.000, Horus is the name of one of the sons of the God-Emperor of Mankind.
http://wh40k.lexicanum.com/wiki/Horus_Heresy

I know. Warhammer does the now-standard sci-fi folklore mythopoeic mashup thing. I get it. Politically, it's still essentially Pharonic. Even if it wasn't it wouldn't matter (though it is, since it's rigidly theocratic), Horus is a reference to egyptian myth.
Please tell me no one believes the incarnated deity is unique to the Judeo-Christian tradition? See also: Aeneus and the Aeneid, Incarnations of Buddha in Jataka Tales, every third Kung Fu movie
Also, as mentioned, Divine Right of Kings (also in Asia the somewhat analogous Mandate of Heaven). The only thing borrowed from Christian history is the Inquisition. Most of the rest of the Imperium (and the Warhammer 40k world in general) owes more to the Asimov's Foundation Trilogy (and its future religion based on Nuclear Energy or something) than any other book, especially religious ones. The imperial ecumenopolises are likely modelled on Trantor.