President Donald Trump and several top administration officials are joining with a cast of mostly conservative Christian clergy this Sunday on the National Mall in Washington for a prayer gathering billed as a "rededication of our country as One Nation Under God" upon America's 250th birthday.

But some critics call the Rededicate 250 event an effort to "hijack" U.S. history with a false, Christian nationalist narrative — one they say fuses American and Christian identities and threatens a constitutional separation of church and state.

The daylong program is being organized by a nonprofit called Freedom 250. Its website describes it as a public-private partnership "leading the presidential programming for America's 250th anniversary," which culminates with the anniversary of the Declaration of Independence on July 4.

Congressional Democrats have questioned the organization's structure and finances, which they see as a Trump-controlled end run around a separate commission charted by Congress a decade ago to prepare semiquincentennial events.

Top Republican officials promote event

Organizers expect thousands of people to attend Rededicate 250, which will include worship music, prayers and speeches from Cabinet heads and other Republican officials, along with religious leaders and others. Trump and several other speakers are addressing the crowd by video, while others will speak in person. The scheduled participants include Secretary of State Marco Rubio, Defense Secretary Pete Hegseth and House Speaker Mike Johnson, R-La.

"Our founders knew two simple truths," Hegseth said in a promotional video for the event featuring a montage of Cabinet secretaries.

"Our rights don't come from government, they come from God. And a nation is only as strong as its faith," added Hegseth, whose use of Christian rhetoric to justify the U.S. and Israel's war against Iran and in other official settings has drawn scrutiny.

Another promotional video for Rededicate 250 blends various Christian and American imagery — scenes of a cross laid on an American flag, a robed choir, people raising their hands in worship — along with a brief scene of a man praying while wearing a Jewish skullcap. Voices of prominent preachers are heard, one proclaiming, "Faith in God is the value that most shaped America."

Religious leaders on the Rededicate 250 program include several longtime Christian supporters of Trump, among them evangelist Franklin Graham and pastors Paula White-Cain, who heads the White House Faith Office; Robert Jeffress; and Samuel Rodriguez. Also scheduled are Catholic Cardinal Timothy Dolan and Bishop Robert Barron and Orthodox Jewish Rabbi Meir Soloveichik, the only faith leader on the program representing a non-Christian faith.

Musicians on the program include Grammy-winning contemporary Christian artist Chris Tomlin.

Some leading participants portray Rededicate 250 as a Christian gathering.

"I believe it's a moment when the Body of Christ, the church, comes together and will boldly declare that America still needs God," said Georgia pastor Jentezen Franklin in a social media video posted on X. "This is an opportunity for believers to stand together as one nation under God. ... I'm honored that they've asked me to speak and share the Gospel."

Johnson noted that the event comes 250 years after Congress declared May 17, 1776, a "day of Humiliation, Fasting and Prayer" on behalf of the Revolutionary cause.

Critics say event 'hijacked' by Christian nationalism

Critics say Rededicate 250 is shaping up to promote Christian nationalism — whose adherents typically believe that the United States was founded as and should be a Christian nation.

"What should be a broadly unifying celebration has been politically hijacked and wrapped up in this MAGA narrative that tries to rewrite our history and promote the president's agenda," said U.S. Rep. Jared Huffman, referring to Trump's "Make America Great Again" movement.

READ MORE: What to know about the archconservative church Defense Secretary Pete Hegseth attends

Huffman said the movement erases the diversity of America's religious and nonreligious populations throughout its history and threatens the constitutional protections against government-established religion.

The event "would have the founders rolling in their graves," said Huffman, a California Democrat. He co-chairs the Congressional Freethought Caucus, which emphasizes separation of church and state.

"They have narrowly defined what it means both to be American and to be Christian, and they are wrapping that in the official sanction of the U.S. government," Huffman said.

He said it's a movement that doesn't speak for all Christians, noting Trump's recent sparring with Pope Leo XIV.

Conservative Christians cheer multiple Trump initiatives

The Rededicate 250 event is occurring in tandem with other White House initiatives appealing to Trump's loyal base of conservative Christians, particularly white evangelical Protestants.

Several participants — including Graham, White-Cain, Dolan, Barron and Soloveichik — also serve on the Religious Liberty Commission. That Trump-appointed panel is preparing a report on its findings after a year of hearings, many of which were focused on conservative Christian and right-leaning political grievances. Its chair, Texas Lt. Gov. Dan Patrick, a Republican, repeatedly denies that the Constitution establishes a separation of church and state.

Several participants in Rededicate 250 joined with Trump himself in a Bible-reading marathon.

And a separate Trump administration task force recently alleged discrimination against Christians under Democratic President Joe Biden — a report criticized by progressive groups as "advocacy dressed up as investigation."

That report alleged that such a bias resulted in heavy fines imposed on two Christian colleges — Grand Canyon University for allegedly deceiving thousands of students over program costs, a decision later reversed, and Liberty University for its handling of crime statistics and sexual assault cases. Choirs from both colleges are performing at Rededicate 250.

Beliefs about Christian nationhood

About 2 in 10 U.S. adults and about one-quarter of Republicans, said the federal government should declare Christianity the official religion of the nation, according to a Pew Research Center survey conducted in April.

Some 43% said the government should not do so, but should promote Christian values, while 38% said it should do neither. The report said 13% of U.S. adults and 18% of Republicans said the government should stop enforcing the separation of church and state.

Historians generally agree that the founders' religious beliefs varied, that the U.S. Constitution doesn't establish an official religion and that it was significantly influenced by Enlightenment thinkers.

The Freedom From Religion Foundation, which advocates a strict separation of church and state, hopes to stage a demonstration elsewhere in Washington on the day of the rally.

"This is the government putting on a Christian nationalist event," said Annie Laurie Gaylor, the foundation's co-president. "Even if it is accepting private money for it, it's still putting it on. It's outrageous."

Brian Kaylor, a Baptist pastor and president and editor-in-chief of Word&Way, a progressive site covering faith and politics, said that while the Continental Congress did call for a day of prayer, the founders crafted the Constitution to prevent the establishment of religion. Two early presidents, Thomas Jefferson and James Madison, thought such official events were harmful to religion, he wrote.

The event "simply doesn't represent what type of nation the founders later decided to create," Kaylor wrote.