I was raised Catholic and somewhere along the line, started to question this ancient book called the Bible. The more experiences I had, the less reliable this book seemed. One of my old college roommates, a caring, loving, hilarious human being, is in a beautiful committed relationship and has 1.5 kids (the .5 is still baking) with the love of her life - who just happens to be another female. The bible tells me this is a sin - wrong and evil. My experiences tell me she is an amazing person. The bible talks of right and wrong. My experience tells me more often than not there are shades of gray to most situations.
Once I got into yoga, my confidence in myself escalated exponentially. I began to trust that I did know myself best. That true beliefs were individual and couldn't be dictated by anyone else - they had to be felt in the gut. Most importantly, I learned only I could determine what was right for me, regardless of if it was written in some book thousands of years ago. What took me years to learn is summed up nicely by Buddha:
"Believe nothing, no matter where you read it or who has said it, not even if I have said it, unless it agrees with your own reason and your own common sense.” – Buddha
I am not saying yoga and religion cannot be practiced together. But I do think the recent popularity of yoga is scary for religious leaders, and rightfully so. The more people who question what they once "believed" so willingly, the more people who may be spending their Sunday mornings with their families, helping deserving causes, taking in nature, etc - whatever they feel is most important for them at that moment instead of what their religion dictates they must do.