Every time Joe Biden has been sworn into office since he became a senator in 1973, he has rested a hand on the same giant Bible.
The 5-inch thick Bible made its most prominent appearance in its 127-year existence Wednesday when Biden, 78, took his oath as the nation's 46th president during the inauguration ceremony in Washington, D.C.
The Bible, which is adorned with a Celtic cross on its cover, has been in Biden's family since 1893.
"It's just been a family heirloom on the Biden side of the family, and every important date is in there," he told late-night host Stephen Colbert last month. "For example, every time I've been sworn in for anything, the date has been on that and is inscribed on the Bible."
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Biden's wife, Jill, held the large Bible when Biden is sworn in as president.
"Have you been working out?" Colbert joked to her.
Biden was first seen with the Bible when he was sworn in as a senator in Delaware in 1973 at 30 years old, and the family heirloom has made an appearance at his subsequent swearing-in ceremonies as senator and eventually vice president.
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It was last present in 2013 when Biden was sworn in by Justice Sonia Sotomayor for a second term as vice president after President Barack Obama's reelection. Sotomayor also made history in that ceremony as the first Hispanic person to administer an inaugural oath of office.
Biden was sworn in for his first term as vice president on the family Bible, too. His late son, Beau, who died of brain cancer at 46 in 2015, also used it when he was sworn in as Delaware's attorney general in 2007.
Biden has often spoken about his faith, and he and his family have frequently attended Mass on historic occasions like his swearing-in as vice president. On Election Day in November, he attended Mass at St. Joseph on the Brandywine Roman Catholic Church in Greenville, Delaware, before visiting his son Beau's grave.
Last month, he attended Mass with his wife at St. Joseph on the Brandywine before visiting the graves of his first wife, Neilia Biden, and their 13-month-old daughter, Naomi, on the 48th anniversary of their deaths. The mother and daughter were killed in a car crash on Dec. 18, 1972, when a tractor-trailer struck their car while Neilia was taking their children to pick out a Christmas tree.
As Biden prepared to place his hand on the family Bible on the most significant day of his political career, he spoke to Colbert about the gravity of the moment.
"It's been more a sense of ... obligation than wanting to live in the White House," Biden said. "The country we've been the last four years is not who we are, and we have to get back to who we are."
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