Fallible Religions

Last weekend I was enjoying a few drinks with three friends discussing social, political and economic issues. We found ourselves in agreement on most issues brought to the table until we reached religion. One of my friends took the helm of the religious ship and started steering, one person always tries to do that. After a few hundreds jabs, arguments and opinions and just when Captain God has ran out of answers on why religion is absolutely ridiculous, he pulled out his ace in the hole and made on final attempt at winning the battle by saying "You cannot judge a certain religion by its followers, in most cases, they were not what was intended."

After that blow, I resigned the conversation, not because I did not have an answer to that but because the conversation just took a philosophical turn that would ignite a whole new topic that would prove my money on drinks that night to be a waste because it will surely leave me sober. So I decided to leave my answer for Fearful Thought:

You absolutely can judge a religion by its followers, because gods by definition are self-proclaimed infallible. If a god is infallible, that means she built her religion for every person of every era. If that is true then surely god would account for human behavior and how humans would respond to the message of that particular religion. If followers of a certain religion are not correctly abiding the rules of said religion then that can only be explained by the shortcomings of that religion [and its god] to correctly predict human behavior and build its message around that.