Warnock, the senior pastor of Ebenezer Baptist Church in Atlanta, was part of a group called the "Christian Peace Witness for Iraq," seeking to "foster a serious nationwide discussion on following Jesus in matters of conscience and duty, violence and nonviolence, war and peace" through its "Conscience in War" project.
Warnock spoke at a March 2007 Christian Peace Witness event at the National Cathedral in Washington, D.C., according to multiple reports. One video from Fox 5 D.C. showed Warnock (time stamp: 2:05) speaking at the altar of the cathedral during the event.
An invitation to the event read: "As followers of Jesus Christ....our faith compels us to make our voice heard — to repent of our complicity with the invasion and occupation of Iraq and to renew our commitment to peacemaking."
"We need a surge in troops in the nonviolent army of the Lord," Warnock said during the event, according to a 2007 episode of NPR's "Weekend Edition" covering Christian-led protests against the U.S. invasion of Iraq. "The danger confronting America is not that we may lose the war. The real danger is that America may well lose its soul."
Warnock did not immediately respond to an inquiry from Fox News.
At the same event, the reverend said Congress had "proven to be totally morally inept to intervene and too politically compromised to act with real conviction," according to a March 2007 report from the National Council of Churches, USA (NCC) News Service.
"Our soul's in danger," Warnock said, also referencing the 2005 Hurricane Katrina disaster, as NCC News reported. "When you have the money to bomb and rebuild Baghdad but no money to rebuild New Orleans, soul's in danger."
Warnock’s speech echoed similar statements made by Martin Luther King Jr., who had said, "A nation that continues year after year to spend more money on military defense than on programs of social uplift is approaching spiritual death."
2007 was the deadliest year for U.S. soldiers in Iraq with as many as 899 U.S. military members killed that year, according to multiple reports at the time.
Warnock also spoke at a 2009 "White House worship and witness" event with Christian Peace Witness, where one faith group called on the Obama administration to repent for the Iraq war.
Presbyterian Peace Fellowship executive director Rick Ufford-Chase, who attended the 2009 event, said the fellowship was "hopeful" that President Obama "or a spokesperson" would join the group "for worship or to receive the bread," which represented repentance for the war, according to a press release from the Presbyterian Church USA.
In 2009, at least 11 out of 148 American troops killed in Iraq were from Georgia, VOA News reported.
Warnock came under fire in November after a 2011 sermon resurfaced during which he said nobody could serve "God and the military."
"America, nobody can serve God and the military," Warnock said during the sermon titled "When Truth Meets Power." "You can't serve God and money. You cannot serve God and mammon at the same time. America, choose ye this day who you will serve. Choose ye this day."
Warnock has defended the reference, telling Fox News, "This sermon is based on a biblical verse that reads, 'No man can serve two masters…Ye cannot serve God and mammon,' a biblical term for wealth."
"Reverend Warnock was speaking about the need to commit to moral life before pursuing other priorities," Warnock's communications director, Terrence Clark, said in a statement. "As the video of the congregation’s response makes clear, this is another blatant effort by [Georgia Sen.] Kelly Loeffler to take Reverend Warnock’s words completely out of context. Given her own decision to spend her first days in the U.S. Senate profiting off the pandemic, perhaps she should watch the sermon more closely."
Loeffler slammed Warnock's reference as "despicable, disgusting and wrong" in a Nov. 18 tweet after footage from Warnock's 2011 sermon resurfaced. The Georgia Republican did not immediately respond to an inquiry from Fox News regarding Warnock's Christian Peace Witness speeches.
Fox News' Caitlin McFall contributed to this report.