Modern-day religion is best thought of as a vehicle for one’s spirituality. Before ever stepping into church as a modern adult, one needs either a great deal of either prior familiarization or focused deliberation.
The decision to shoehorn spirituality into religious forms is not to be taken lightly. An example of a form of spirituality that would probably never work in church is the one depicted in Quentin Tarantino’s True Romance. The main character sees Elvis and takes advice from him.
It looks like “just” an imaginary friend dynamic and not spiritual, but it’s really just the same thing psychologically, as having a close personal relationship with Jesus. Clarence displays character traits clearly intended to convey divine favor. One could imagine Clarence later on replacing Elvis with Jesus and going to a Christian church.
Spirituality isn’t jealous, so perhaps Clarence is also a Christian, meaning he also believes in Jesus. He just doesn’t hallucinate Jesus in the mirror and Jesus never tells him to kill mobsters. Humans believe in things because they find meaning in them, and Clarence would just find more meaning in what Elvis says than what he imagines Jesus has to say. Jesus is far, Elvis is near.
This dynamic is behind the recession of religion into the background over the last few hundred years. It’s just easier to find meaning in your own forms and your own beliefs than in ones handed down to you, especially when those forms were created to fit the needs of Roman citizens circa 500 AD rather than suburban Americans.
Eventually people felt so far away from Christianity that they threw away the forms entirely. But we’re a long way from actually discarding Christianity, much of our culture is predicated on the archetypes and storylines and mythic elements of Christianity, with some Greek and Roman mythic elements tossed in for flavor.
Meaning is still being found in archetypes and stories and myths and things like spiritual beliefs are still getting constructed, they’re just formed less and less these days around the forms of monotheistic religions which once acted like a big tent under which anyone of a spiritual bent could find a common language to discuss with others with. These days people are more likely to reach for Star Wars rather than the Bible.