It was fired by the Catholic League, responding to this billboard put up outside of Manhattan by a group of atheists.

Details, from the New York Times:

The Catholic League for Religious and Civil Rights has responded to a Christmas-debunking billboard sponsored by American Atheists just outside the New Jersey entrance of the tunnel by erecting one of their own at the other end.

The new billboard reads “You Know It’s Real: This Season Celebrate Jesus.” It shows a warm nativity scene, with Joseph and Mary staring lovingly down at an infant Jesus lying in straw in a splash of light. “Merry Christmas from the Catholic League” appears in smaller type to the right of the image and above a Catholic League insignia.

The billboard promoting atheism went up last week along I-495. It reads “You know it’s a myth. This season, celebrate reason!”

Bill Donohue, president of the Catholic League, a lay civil rights organization that receives no church financing, said that an anonymous donor in Manhattan came up with the money — about $18,500 — to buy the 26-by-24-foot billboard at Dyer Avenue and 31st Street for about a month. It went up Monday afternoon.

Mr. Donohue said the billboard was not intended as “a statement against atheists or agnostics, most of whom are good people,” but as a repudiation to “aggressive, militant atheism” that he believes is growing increasingly prevalent in America.

Joseph Zwilling, the director of communications for the Archdiocese of New York, said that while the Catholic League does not speak on the Archdiocese’s behalf, he thought the billboard “articulated the reality that Catholics and Christians believe in Jesus.”

“Jesus historically lived, there’s no doubt about that,” Mr. Zwilling added. “He was a real person in a real time, and for Catholics and Christians we believe he was the son of God.”

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