On Thursday, during the swearing-in ceremonies for members of the new 116th Congress, one of the more interesting texts from the Library of Congress' archives made its second-ever appearance on the floor of the Capitol building: Thomas Jefferson's 1734 English translation of the Quran, Islam's holiest text. Rashida Tlaib, one of the first two Muslim women ever to join Congress, chose to take her oath on the historic book. As Speaker of the House Nancy Pelosi swore in Tlaib, the Democrat from Michigan placed her hand on the faded cover of the founding father's Quran and took an oath to "support and defend the Constitution of the United States against all enemies, foreign and domestic."
For much of U.S. history, members of Congress—as well as witnesses in court, firefighters, and presidents—have chosen to swear on a copy of the Bible when taking their oaths. However, the 116th Congress is the most diverse in history, and the texts used in swearing-in ceremonies on Thursday were as diverse as the new class. Jefferson's Quran joined more than a dozen other religious and non-religious texts that were used by new representatives and senators to take their oaths: Ilhan Omar, a Democratic representative from Minnesota and the other first Muslim woman to serve in Congress, also opted for a Quran. Krysten Sinema, the new Democratic senator from Arizona, opted for a law book that contained both the U.S.'s and Arizona's constitutions (Sinema is the only person in the Senate to state that she is "religiously unaffiliated.")
Though the Bible is by far the most common object used in swearing-in ceremonies, the Constitution makes no requirement that the Christian text—or, indeed, any other text or object—be used. Article VI, Clause 3 of the Constitution requires that senators and representatives "be bound by Oath or Affirmation" to support the Constitution, but that same clause ends with the declaration that "no religious Test shall ever be required as a Qualification to any Office or public Trust under the United States."
Jefferson's Quran made its first appearance in the Capitol in 2007, when Keith Ellison of Minnesota became the first-ever Muslim member of Congress and chose to use the archival Quran to take his oath. Ellison's swearing-in ceremony caused serious controversy among many on the Christian Right, who, despite the Constitution's clear language on the matter, argued that the Bible was the only text that could be used to swear the oath of office. The conservative columnist Dennis Prager wrote that Ellison's decision to use anything other than the Bible would "do more damage to the unity of America ... than the terrorists of 9/11."
The tradition of using the Bible in oath-taking likely comes from ninth-century England, where, without dedicated governmental centers, the altar of a church often served as the courtroom for oaths and contracts. Gospels began to be used in the contractual ceremonies, and, eventually, the tradition migrated into English courtrooms before crossing the Atlantic into American legal ceremonies. Though oaths are indeed religious in origin, the Constitution makes clear that the oath can be replaced with an "Affirmation," which substitutes the religious language (the "I swear" and "So help me God") with a secular affirmation (for example: "I affirm to tell the truth, the whole truth, and nothing but the truth").
Though religious diversity among elected officials has highlighted the tradition in recent years, there are many historical examples of the Bible being absent from swearing-in ceremonies. President John Quincy Adams, like Sinema, swore his oath of office on a book of a law instead of a religious text in 1825. When President William McKinley was assassinated in 1901, Vice President Theodore Roosevelt took his oath of office without any oath-object whatsoever, as no Bible could be quickly found. In 2013, Tulsi Gabbard became the first Hindu member of Congress and swore her oath on a copy of the Bhagavad Gita.
Other public officials have opted for a non-religious, non-traditional object: In 2014, Suzi Levine, the then-incoming ambassador to Switzerland and Liechtenstein, swore her oath of duty on a Kindle. In 2018, Mariah Parker swore in on a copy of The Autobiography of Malcolm X when she took her oath as Athens-Clarke County commissioner in Georgia.