A giant ad promoting atheism has been unveiled on a billboard in northeast Calgary.

Previously seen in Vancouver and Sudbury, the ad informs Calgarians that "praying won't help."

“I know that some people are immediately going to be offended by it and see it as an attack on religion,” Nate Phelps, Alberta executive director of the Centre for Inquiry, the group behind the ad, told Metro Calgary.

“But I hope that some religious people are at a point in their life that they’re willing to look at this as a challenge, and consider it.”

The billboard features a young woman at her computer with the caption “Jenn 13:1 - Praying won’t help. Doing will. Without God. We’re all good,” and is located on the south side of 3603A Edmonton Tr. N.E.

Story continues below the slideshow

Loading Slideshow...
  • In this Sept. 9, 2010 photo, a billboard erected by atheists in Oklahoma City reads " Don't believe in God? Join the club". Nick Singer, the coordinator of a local atheists' group called "Coalition of Reason," recently received $5,250 from its national counterpart to erect the billboard along Interstate 44 near the Oklahoma State Fair. Oklahoma ranks eighth in the nation for percentage of residents who self-identify as Christians (85 percent), according to an analysis of the 2008 U.S. Religious Landscape Survey conducted by the Pew Research Center's Forum on Religion and Public Life. (Sue Ogrocki, AP)

  • Atheist billboard on Capital Blvd. in Raleigh, North Carolina, can be seen March 29, 2011. (Chris Seward, Raleigh News & Observer / MCT)

  • A billboard sponsored by an atheist group is displayed near the entrance to the Lincoln Tunnel in North Bergen, N.J., Wednesday, Dec. 1, 2010. Now, the Catholic League has countered by putting up its own billboard near one of the tunnel's New York City entrances. (Seth Wenig, AP)

  • An atheistic billboard in Chicago. (<a href="http://www.flickr.com/photos/ericingrum/4038228725/" target="_hplink">Eric Ingrum</a>, Flickr)

  • A billboard sponsored by a Catholic group is displayed near an exit of the Lincoln Tunnel in New York, Wednesday, Dec. 1, 2010. Similarly, a billboard sponsored by an atheist group is displayed near the tunnel's New Jersey entrance. (Seth Wenig, AP)

  • <a href="http://www.huffingtonpost.com/2012/03/13/atheist-slavery-billboard-pennsylvania-raises-tempers_n_1342268.html">From RNS' Diana Fishlock</a>: A billboard erected in one of the Harrisburg, Pa.'s most racially diverse neighborhoods featured an African slave with the biblical quote, "Slaves, obey your masters." It lasted less than a day before someone tore it down.

  • An atheist group <a href="http://www.huffingtonpost.com/2012/03/07/american-atheists-myth-billboard-brooklyn-jewish-rejected_n_1327527.html">was blocked</a> from erecting a billboard in a heavily Jewish neighborhood in Brooklyn, New York.

“There exists an idea out there that you can’t be good, you can’t be hopeful, you can’t be positive, you can’t lead a good life unless you subscribe to some religious ideology,” Phelps told 660 News.

Some Reddit users were quick to claim hypocrisy in the ad, however.

"This is stupid because it's likely the people who are putting up that billboard would be the type to tell Christians to not shove their beliefs down their necks," wrote user Yojimbe.

"If this sign was fashioned against any other group it would be immediately shot down and that's where I take issue," said urahozer.

Others, however, believe there's a place - and even a need - for the ad in Calgary.

"It'll be nice to have something on the other side displayed for once. I'm rather tired of fake images of aborted fetuses, so while Jen 13:1 could have been done better, I'll take it," countered Wistfuljali, referring to ads placed around Calgary by anti-abortion groups.

"While I think they could have used a better slogan or mantra for it, the message behind it isn't about believing or not believing. It's about believers respecting those who don't, and challenging the social stigma attached to non-theists," said jimmyjames88.

The same ad was banned in Vancouver late last year, after Pattison Outdoor - a company who owns many Vancouver billboards - refused to run it. Instead, the ads found a home on the city's downtown transit shelters and on billboards in Burnaby.

Also on HuffPost: