religion, for me, is a complete life experience, both a feeling and definitely a rational, philosophical system of thought.
it is to live in accordance with the virtue of αγάπη or caritas. that is, the virtue called charity. (not to be confused with almsgiving.) it is this virtue, this type of love that was meant when it was written that "god is love."
(english is utterly inadequate in spiritual vocabulary, and there is only one word for "love" besides. hence translations of spiritual writings with no annotations and no other context given are especially problematic. compounding the issue is that most people, religious or not, are ignorant of these contexts; perhaps they've read the bible, for example, but that's all they've read--it's not everything, and perhaps isn't even very useful on its own, in english, without any context.)
and while it may be true that god is love, god has been morphed into other things by ignorant, selfish people. when nietzsche said that god is dead and we have killed him, that is what he meant: the idea of god just ain't what it used to be. in fact, it takes a very humble, philosophical mind to think on the idea of god. (unfortunately, too many people think religion is the antithesis of rational thought.) this is what i mean when i say that religion has been oversimplified and popularized. there is the image of god, seemingly a god of flesh and bone, that is, a god that "exists," as creator of the universe, sitting up in "heaven" (as if it were a place) on a throne, looking down on us and judging us. and this is decidedly not what is meant when we discuss god.
to be religious is to reject moral relativism for the sham it is, to know the beauty of the good and the ugliness of evil, and to love (but not necessarily like) unconditionally, which is what god is. ('god is love.') you read correctly: it is not only about becoming a "better person," it is about becoming god-like.
and that is a lot harder than it sounds.
it is NOT about passively "believing" something without giving it any thought. it is NOT about "saying" a prayer and expecting all your material "problems" to be resolved.
finally, i will say this. there is no such thing as an atheist. there are only those who are truly religious and those who are falsely religious, those who have taken some other idol and lifted it up to be their god. (in much of western europe and north america, especially in recent days, freedom of speech comes to mind. though, for all the moral relativists in those same areas, i don't see how they can authentically value any such thing... for all their rationalism... it makes no sense.) as such, let us not talk of christians, jews, muslims, buddhists, hindus, taoists, atheists, agnostics, or any other such "religions." all of those are better understood as cultural traditions, albeit divinely inspired ones. you will find truly religious and falsely religious peoples in all of them, and that is the important distinction. the "divine," or the "other," or the "godhead" is the same for everybody, whether it is acknowledged or not.