Here's a theory. Most people encounter problems that seem (and maybe are) too complex to solve. When that happens, we often comfort ourselves by focusing on less complex "issues", and we prefer finger pointing to looking in mirrors. i.e. It's way more comfortable to criticize people who are different than to improve ourselves. The bottom line is that it feels good to be told we're somehow superior to others, and religious leaders sometimes feed their followers these messages because it keeps them coming back for more. They've discovered this message appeals to their followers, so they use it.
Here's a theory. Most people encounter problems that seem (and maybe are) too complex to solve. When that happens, we often comfort ourselves by focusing on less complex "issues", and we prefer finger pointing to looking in mirrors. i.e. It's way more comfortable to criticize people who are different than to improve ourselves. The bottom line is that it feels good to be told we're somehow superior to others, and religious leaders sometimes feed their followers these messages because it keeps them coming back for more. They've discovered this message appeals to their followers, so they use it.