Organizers of the National Day of Prayer are encouraging the nation's governors to ignore threats by anti-religion opponents and observe this year's day of prayer, scheduled for May 5.

They say they're not concerned an appellate court will uphold a challenge brought by the The Freedom from Religion Foundation.

The group of atheists and agnostics say it's not the government's business to tell people to pray -- even though throughout U.S. history, presidents have issued proclamations calling on Americans to seek God's wisdom and blessing.

Last year, a district court judge ruled the day of prayer violates the Constitution. The ruling is on hold while an appeals court considers the FRR's challenge.

In the meantime, the Alliance Defense Fund is telling public offiicials that asking their constituents to pray is legal.

"We prepared a letter for the governors around the country to assure them that they can recognize the National Day of Prayer, and that it is a perfectly legal activity for them to do and something our founders have done from the beginning of our country, and it is a practice we've maintained up until this very day," explained Kevin Theriot, an ADF attorney.

The theme for the National Day of Prayer this year is "A Mighty Fortress is Our God."