Bush, speaking at the 52nd National Prayer Breakfast, said in coming together the debates of the working day were put aside and "we recognize our dependence on God and pray with one voice for His blessings on our country."
"We're the capital of the most powerful nation on Earth, yet we recognize the limits of all earthly power," he said.
Bush lauded the American character and its heritage of faith and religious tolerance, a tolerance shown in Iraq by American troops of all faiths and creeds who help rebuild mosques and reach out to the people in friendship.
"In prayer, we ask for wisdom and guidance," he said.
Bush and other guests at the Washington Hilton were entertained by a Ugandan children's choir and Christian music diva Twila Paris.