I think that in many ways, religion worships mystery. When I look at the history of religion, one of its main purposes seems to be to explain the unexplainable. Where did we come from? Well, Father Time slept with Mother Earth. Or Kukulkán and Tepeu made humans from maize. Or Yahweh made everything in six days. Where do we go when we die? Well, we go to the house of Hades. Or we spend eternity in some sort of paradise. Or... nothing happens. We're just dead.
So, when I say religion worships mystery, I mean that it derives its raison d'être from humans' inability to explain the world. In ancient mythopoeic religion, humans explained natural phenomena by anthropomorphizing them. Everything had a persona behind it. There were river gods, rain gods, mountain gods, fertility goddesses, plant gods-- everything had a god behind it. These gods served to explain the natural world, which otherwise seemed completely nonsensical.
In time, however, humans developed better ways of explaining things. For the Greeks, this was philosophia-- the love of wisdom. During the European Renaissance, "natural philosophy" was the study of the natural world. And this natural philosophy became what we now call science. I don't think I have to reiterate the story of how Christianity fought against science, how people like Galileo were persecuted for being so brazen as to undercut the church's monopoly on "truth." There's a reason that religion was so threatened by rational inquiry. If there were other ways of finding out knowledge, then religion was entirely unnecessary.
Religion stifles knowledge and inquiry. It worships the gaps in our knowledge by filling them with gods. It tries to get us to be satisfied with answers that aren't answers, to persuade us that we don't need to know, don't need to ask why and how and when, tries to convince us that the ultimate virtue is ignorance. But they don't call it ignorance. They call it faith.
And religion has been very successful in pulling this off. It has succeeded in convincing people that without ignorance, life is meaningless. Without faith, without mystery, without God, what meaning is there to existence? Without the promise of eternal reward and the threat of eternal damnation, why should one treat one's fellow human beings well? This is the great lie of religion. Ignorance and mystery add nothing to life except fear and misery.
I'm a musician. For a time, I thought that studying music theory would remove the sublimity of music. Oh, how mistaken I was! I'll admit, my knowledge of music theory is limited, but what I do know has not diminished my admiration for music one bit. On the contrary, my understanding of scales and intervals and overtones has enhanced my love of music.
Human beings love the experience called wonder. But there are two kinds of wonder. One comes from ignorance, and the other from understanding. Having experienced both, I can say that the wonder of understanding is much deeper, much more beautiful, and infinitely preferable to the wonder of ignorance. God is not necessary to explain the universe. We don't need religion to be good. These artificial, two-dimensional explanations only cheapen our experience of the beautiful universe that we are a part of.