Bumper Sticker Theology

I saw a bumper sticker the other day that said, "God is too big to fit into any one religion." Here's the problem I have with that saying. And I think it may surprise you what I say. God's not concerned with religion anyway. God is concerned about hearts and what is spiritual. And I think, at least in our culture today, and perhaps it's always been this way, the two are very different.
I think the Jews of Jesus' day thought they were religious. Jesus told them, "You honor me with your lips, but your hearts are far from me." This is a quote from the Old Testament. In other words, they had the same problem then. I associate religion with rules and following the rules because they are the rules and you know what happens when you don't follow the rules. Maybe this is faulty thinking, but it's where I am. Jesus spent the entire Sermon the Mount saying that it's not about the rules. You can follow all the rules and still not be spiritual.
That's why I have a problem with the bumper sticker. Perhaps we need to understand that God doesn't fit into religion....period. It doesn't have anything to do with Him being too big. It's not what He wants in the first place. I hope your day is a good one.