Almost all religion begins with a specific encounter with something that feels “holy” or transcendent: a place, an emotion, an image, music, a liturgy, an idea that suddenly gives you access to God’s Bigger World. The natural and universal response is to “idolize” and idealize that event. It becomes sacred for you, and it surely is. The only mistake is that too many then conclude that this is the way, the best way, the superior way, the “only” way for everybody—that I myself just happen to have discovered. Then, they must both protect their idol and spread this exclusive way to others. (They normally have no concrete evidence whatsoever that other people have not also encountered the holy.)
The false leap of logic is that other places, images, liturgies, scriptures, or ideas can not give you access. “We forbid them to give you access; it is impossible,” we seem to say! Thus much religion wastes far too much time trying to separate itself from—and create “purity codes” against—what is perceived as secular, bad, heretical, dangerous, “other,” or wrong. Jesus had no patience with such immature and exclusionary religion, yet it is still a most common form to this day. Idolatry has been called the only constant and real sin of the entire Old Testament, and idolatry is whenever we make something god that is not God, or whenever we make the means into an end. Any attempt to create our own “golden calf” is usually first-half-of-life religion, and eventually false religion.