For the longest time, the question just sat there on his screen. Cursor blinking. Waiting quietly, like a patient priest in a confessor's box.

Religious Views: _____.

Creating a Facebook profile for the first time, Eric Heim hadn't expected something so serious. He had whipped through the social network Web site's questionnaire about his interests, favorite movies and relationship status, typing witty replies wherever possible. But when he reached the little blank box asking for his core beliefs, it stopped him short.

"It's Facebook. The whole point is to keep it light and playful, you know?" said Heim, 27, a college student from Dumfries, Va. "But a question like that kind of makes you think."

Such public proclamations of beliefs used to require a baptism in water, or a circumcision, or learning the Five Pillars of Islam. Now Facebook users announce their spiritual identity with the stroke of a few keys. And what they are typing into the open-ended box offers a revealing peek into modern faith and what happens to that faith as it migrates online.

Of its 250 million users worldwide, Facebook says, more than 150 million people choose to write something in the religious views box.

Amid the endless trivialities of social networking sites — quotes from Monty Python, the Stephen Colbert for Prez groups — the tiny box has become a surprisingly meaningful pit stop for philosophical inquiry.

Millions have plumbed their innermost thoughts, struggling to sum up their beliefs in roughly 10 words or less. For many, it has led to age-old questions about purpose, the existence of the divine and the meaning of life itself.

Some emerge from the experience with serious answers. George Mason University student Travis Hammill, 19, spent several days distilling his beliefs into this sentence: "Love God, Love Others, Change the World."

Others try to deflect the question with humor.

"Pastafarian," typed Maddy Gillis, 20, of Kensington, Md., invoking a popular pseudo-religion that venerates a "Flying Spaghetti Monster."

The religious views box debuted in 2006, two years after Facebook's launch. Before that, users who talked about faith did so mostly in the "About Me" area.

The most popular faith professed is "Christian" and the various denominations associated with it. The second most popular entry is "Islam," followed by "Atheist." Interestingly enough, "Jedi" makes an appearance at No. 10.

Fear of judgment often plays an outsize role in how young adults express their religious views online, said Piotr Bobkowski, a doctoral student at the University of North Carolina who is conducting a two-year survey of religion on MySpace.

"It's Facebook. The whole point is to keep it light and playful ... But a question like that kind of makes you think."