President Bush said Thursday that America's history is inexorably tied to prayer.

"America is a nation of prayer. It's impossible to tell the story of our nation without telling the story of people who pray," Bush said during a White House celebration of the National Day of Prayer. "At decisive moments in our history and in quiet times around family tables, we are a people humbled and strengthened and blessed by prayer."

Bowing his head many times as Christian and Jewish leaders offered prayers, the president thanked those who pray for him, calling it the greatest gift a citizen can offer him.

"In my travels across the great land, a comment that I hear often from our fellow citizens is, `Mr. President, I pray for you and your family.' It's amazing how many times a total stranger walks up and says that to me," Bush said. "You'd think they'd say, `How about the bridge?' Or, `How about filling the potholes?' No, they say, `I've come to tell you I pray for you, Mr. President'."

Bush was careful to also honor those who choose not to pray, or join any religion.

"We are a people united by our love for freedom, even when we differ in our personal beliefs," the president said. "In America, we are free to profess any faith we choose, or no faith at all."