WASHINGTON -- The inauguration is a political affair that also includes spiritual components. In addition to prayer, another tradition is the Bible used for the official oath of office.
It's a tradition that dates back to the very first president.
George Washington started the custom in 1789. A newspaper reported he bowed and kissed the Bible out of reverence.
Since then, four presidents have used Washington's more than 220-year-old book at their swearing in.
After choosing members of their cabinets and the policies they'll pursue, one of the decisions a new president must make is what book will be used for the inauguration. While the Constitution does not require the Bible, it's a time-honored tradition that often gives a glimpse into the president's spiritual life.
In 2005--like many presidents--George W. Bush used a family Bible, opened to a passage in Isaiah, which reads: "They that wait upon the Lord shall renew their strength; they shall mount up on wings like eagles."
Ronald Reagan took the oath on his mother's well-worn Bible, opened to Second Chronicles 7:14, which reads: "If my people who are called by my name, shall humble themselves, and pray, and seek my face, and turn from their wicked ways; then will i hear from heaven, and will forgive their sin, and heal their land."
Dwight Eisenhower's Bible from West Point was opened to that same scripture. He also used the Washington Bible opened to Psalms, the book most referenced at Presidential inaugurations.
Eisenhower wasn't the first with two Bibles. Harry Truman started the practice, followed by Richard Nixon and most recently President Obama in his second inaugural.
His choices marked the 150th anniversary of the Emancipation Proclamation with the Bible Abraham Lincoln used at his first inauguration and the 50th anniversary of the march on Washington with Martin Luther King Jr.'s Bible.
Several presidents did break tradition: Hayes, Arthur and Teddy Roosevelt didn't use a Bible, or anything for that matter.
Quincy Adams, though a devout Christian, took his oath on law books and the Constitution.
An iconic photo of Lyndon Johnson looks like his hand is on the Bible, but it's in fact on John F. Kennedy's catholic book of prayers, which was left on Air Force One before his assassination.
"Johnson was not Catholic but he swore in on that. Interestingly, years later, when Gerald Ford was on Air Force One, when he was president, he asked also for a Bible, just for comfort. He couldn't find a Bible on Air Force One, and from then on decreed that there should be a Bible on Air Force One and there has been one ever since," said presidential historian Tevi Troy.
So what about America's 45th president? In 2012, Donald Trump told CBN News he receives Bibles from the public.
CBN News has confirmed that when Donald Trump takes the oath of office, he will use the Bible his mother gave him as well as the Bible Abraham Lincoln used when he took his oath of office, continuing a long-standing bipartisan inaugural tradition that signals a new beginning.