Here is dictionary.com's first definition of religion:
a set of beliefs concerning the cause, nature, and purpose of the universe, especially when considered as the creation of a superhuman agency or agencies, usually involving devotional and ritual observances, and often containing a moral code governing the conduct of human affairs.
While I wish this definition included the community aspect of most religions, it's a decent enough definition to go by. Anyone who says Christianity is NOT this is insane, or a liar. The only way to get around this is to, essentially, change the definition of the word religion. The common counter-arguments are "religion focuses on rules, we focus on forgiveness," and "religion divides, we unite". These are, at best, foolish things for a christian to say. The first 5 books of each biblical canon are collectively called "the Law". While Genesis has a lot of stories, and Exodus has one long story, both books have plenty of rules contained in them. And the next three books (Leviticus, Numbers and Deuteronomy) when they aren't recounting genealogy, are exclusively about rules. Even Jesus, the one who introduced the idea of forgiveness to the religion, brought in new rules: no divorce without adultery, love Jesus above all else, etc. To add insult to injury, he even added new rules regarding this gift of forgiveness: accept him as your lord and saviour AND follow all the rules AND beg for mercy anytime you make a mistake, and then you can go to heaven. And as for not causing division...you remember a few sentences back when I said "each biblical canon"? There are three, and each thinks that those whose canons have more or less books than theirs are heretical. That's pretty divisive...and that's without mentioning the derision other faiths get from Christians.
But what about us? Is atheism a religion, is it a belief, does it require faith? Well, no. Here, we don't need to look up the definition of the word, it's included in the word itself. "Atheism" is an Ancient Greek word comprised of suffix, prefix and a root word. The prefix "a-" means lacking or without, the root word "theos" is a corruption of the name of Zeus which came to be the generic term for deities in general, "-ism" means belief. So it literally translates to "no god belief" or "no belief in any god". Lacking a belief in one thing doesn't mean we automatically believe the opposite hypothesis with any amount of conviction, especially when the opposite hypothesis is, essentially, "naaaah."
But, even if atheism WAS a belief, it still isn't a religion, still has no faith involved, and would really just be one belief: There is no god. That's it. How does the universe come about? Is it a constant cycle of big bangs and crunches, did aliens from another universe do it, or is their some other cause I am unable to think of? Well, that's up to the individual to decide, we have no book that we all must follow that tells us this. How are we to live our lives? We decide for ourselves, we have no book of rules to tell us what we must do, aside from laws from our own governments, of course; however, even they can be unjust...so should we fight against unjust laws, and if so, which ones are just? We just can't organize any sort of belief system around what we aren't. The only reason we define ourselves that way is because of religious dominance of the culture, and religious agenda pushers trying to push their agenda on everyone. Declaring ourselves "atheist" is a way to push back.
But really, both these arguments ("Christianity isn't a religion" and "atheism is a religion/belief") are covert admissions the atheists have won the intellectual war. Why would they want to distance themselves from religion if it wasn't wasn't all that bad? The fact is that atheists have done a great job of pointing out that religion is a naked emperor, and the religious have inadvertently done an even better job of this than we have. The smartest and most moral amongst the faithful can't help but be ashamed of their association with such an evil and nonsensical thing as religion, but can't let go of the comfort the religion gives them, so they rationalize it as well as they can. (Don't worry christians, yours isn't the only religion that's trying this) As for that second argument, that atheism is a religion, well, it's a rather transparent and childish tactic. They have literally nothing left in their arsenal when they say that, and the best they can do is take us down with them. Imagine two kids arguing about Santa Claus, and one presents definitive proof that Santa is imaginary, and the other says "well, you're just as big of a doody-head for NOT believing in Santa Claus." It's patently ridiculous, but for some reason, that statement is taken seriously when applied to belief in god.
As always, feel free to disagree, but please show me where my logic is flawed, rather than just calling me a cynic or some other such thing.