Some onlookers observed that President Donald Trump didn't place his hand on the Bible when sworn in at his inauguration, prompting questions about how the Bible traditionally factors into the ceremony.
While it is common for incoming presidents to place their hand on a Bible while taking the oath of office, it's not a legal requirement.
Article VI of the U.S. Constitution states that "all executive and judicial Officers, both of the United States and of the several States, shall be bound by Oath or Affirmation, to support this Constitution; but no religious Test shall ever be required as a Qualification to any Office or public Trust under the United States."
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