ONE puzzle of the world is that religions often don’t resemble their founders.

Jesus never mentioned gays or abortion but focused on the sick and the poor, yet some Christian leaders have prospered by demonizing gays. Muhammad raised the status of women in his time, yet today some Islamic clerics bar women from driving, or cite religion as a reason to hack off the genitals of young girls. Buddha presumably would be aghast at the apartheid imposed on the Rohingya minority by Buddhists in Myanmar.

“Our religions often stand for the very opposite of what their founders stood for,” notes Brian D. McLaren, a former pastor, in a provocative and powerful new book, “The Great Spiritual Migration.”

Founders are typically bold and charismatic visionaries who inspire with their moral imagination, while their teachings sometimes evolve into ingrown, risk-averse bureaucracies obsessed with money and power. That tension is especially pronounced with Christianity, because Jesus was a radical who challenged the establishment, while Christianity has been so successful that in much of the world it is the establishment.

“No wonder more and more of us who are Christians by birth, by choice, or both find ourselves shaking our heads and asking, ‘What happened to Christianity?’” McLaren writes. “We feel as if our founder has been kidnapped and held hostage by extremists. His captors parade him in front of cameras to say, under duress, things he obviously doesn’t believe. As their blank-faced puppet, he often comes across as anti-poor, anti-environment, anti-gay, anti-intellectual, anti-immigrant and anti-science. That’s not the Jesus we met in the Gospels!”