(CNN) Whether you know them by heart or have never heard them at all, the 35 words that Donald Trump will speak to become our president will, in some way, impact your next four years. On the occasion of CNN's mini-documentary, "The Oath ," CNN Opinion asked scholars and writers to weigh in on how history and happenstance have shaped the president's oath of office.

Jim Bendat: Thank you, James Madison

The presidential oath of office consists of 35 words:

I do solemnly swear (or affirm) that I will faithfully execute the office of president of the United States, and will, to the best of my ability, preserve, protect and defend the Constitution of the United States.

We can probably thank the nation's fourth president, James Madison, as much as any other person, for that wording. Well before he became president, Madison had earned the nickname "Father of the Constitution," by virtue of his speeches, effective negotiations and successful compromises at the Constitutional Convention in 1787.

Part of the work at that convention involved the writing of the president's inaugural oath. An early version simply stated, "I do solemnly swear (or affirm) that I will faithfully execute the office of President of the United States of America." But Madison and fellow Virginia delegate George Mason believed the nation's chief executive should also be required to make a promise to support the words and meaning of the Constitution. So, on August 27, 1787, the two men moved to add to the oath the phrase, "and will, to the best of my judgment and power, preserve, protect and defend the Constitution of the United States."

Less than three weeks later, the state representatives finalized the oath's wording. They kept almost all of Madison and Mason's amendment, changing only the words "judgment and power" to "ability." It was clear that Madison had made a major contribution to the very oath he would himself recite many years later, at his 1809 and 1813 inaugurations.

With his 1809 ceremony also featuring the first official inaugural parade and the first official inaugural ball, it would seem appropriate to call Madison not only the "Father of the Constitution," but also the "Father of the inauguration."

Nicole Hemmer: The President who took the oath, gave the oath, and still got it wrong

Nicole Hemmer

William Howard Taft holds the distinction of being the only person to both take and administer the presidential oath of office, first in 1909 as president, then in 1929 as chief justice of the Supreme Court. He also holds the distinction of getting it wrong both times.

The first time, his only audience was the US Senate, so the mistake went unnoticed. But the second time, when he was administering the oath to Herbert Hoover, the ceremony was broadcast on radio. And in a schoolhouse in the small town of Walden, New York, a 13-year-old named Helen Terwilliger was listening.

In preparation for the momentous occasion, Terwilliger had memorized the oath of office. She knew the closing words were a pledge to "preserve, protect and defend the Constitution of the United States." So when the chief justice read the oath as "preserve, maintain, and defend," Terwilliger dashed off a note to advise him of his mistake.

Taft sent a letter in reply, admitting he had said the wrong words but arguing Terwilliger's correction was also wrong. "You are mistaken in your report of what I did say. What I said was 'preserve, maintain, and protect.'" Terwilliger was adamant that her version was correct. By that point, the dustup had become a national story, so broadcasters reran tape of the inauguration for the press and then for the chief justice, who finally conceded Terwilliger was correct. Time magazine reported the incident left Taft "highly diverted" but also dismissive, saying the particular words didn't matter much, and would not prevent Hoover from serving as president.

Still, Taft drew a larger lesson about politics in an era when a person's words could be recorded for posterity. "This shows how much more carefully one who is exercising a public duty must now conduct himself." Given that Taft was writing in 1929, his words seem remarkably prescient, and, giving the communications style of the incoming president, remarkably quaint.

Nicole Hemmer is an assistant professor at the University of Virginia's Miller Center, co-host of the Past Present podcast and author of "Messengers of the Right: Conservative Media and the Transformation of American Politics."

Kate Brower: A new role for FLOTUS

Kate Brower

On January 20, 1965, Lady Bird Johnson was not only by her husband's side at the Capitol for his swearing-in ceremony, she became the first first lady to hold the Bible that President Lyndon B. Johnson placed his hand on as he repeated the oath of office. During an emotional ceremony, a little more than a year after President John F. Kennedy's assassination, Lady Bird stood in a bright red coat and hat clutching the Bible that was given to them as a Christmas gift in 1952 by Lyndon's mother. She looked on lovingly at her husband, fully aware of the weight of the office."I stood facing the throng between the chief justice and Lyndon while he took the oath," Lady Bird recorded in her diary. It was President Johnson's idea that his wife, who had made his political career possible, hold the Bible. "I was touched," she wrote. Every president, with the exception of Franklin Pierce, Theodore Roosevelt, and John Quincy Adams, has placed his hand on a Bible at his swearing-in ceremony. At LBJ's swearing-in African-American soprano Leontyne Price sang "America the Beautiful" as civil rights demonstrations engulfed the country.

Less than six years after the Johnsons left Washington, Gerald Ford was sworn in as the 38th president of the United States in an East Room ceremony on August 9, 1974, after President Richard Nixon's resignation. It was an unprecedented moment in history, most famously because it marked the first time a president had resigned from office but also because of a lesser known detail: Gerald Ford became the first president to reference his wife in an inaugural address when he said, "I am indebted to no man and only to one woman, my dear wife, as I begin this very difficult job."

In the modern era, the partnership between presidents and first ladies has become a very public part of the institution of the presidency and the peaceful transfer of power. Thanks, in no small part, to Lady Bird Johnson's very public role, it is hard to imagine an inauguration when the first lady is not front and center.

Kate Brower is the author of the best-sellers "First Women: The Grace and Power of America's Modern First Ladies" and "The Residence: Inside the Private World of the White House." Unless otherwise noted, facts in this piece reflect research from those works.

Akhil Reed Amar: The only "I" in the entire Constitution

Akhil Reed Amar

Some of the words of the presidential oath will come easily to Trump. Others will be harder.

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Here are the easy words for him: "I do ... swear that I will ... to the best of my ability. ..." Unlike say, seats in the Congress or on the court, the presidency is a strikingly personal office, with the entire power of a branch of government vested in and revolving around a single individual. The words "I" and "my" should come easily to Trump's lips because these are strikingly self-centered words and he is unusually self-centered. Interestingly enough, these words in the presidential oath clause are the only first-person-singular words in the entire Constitution, a document that begins, famously, with collective language — "We, the people, ... do ordain and establish..." — and that also elaborates the legislative and judicial branches, which are far less personal than the presidency.

Other oath words may be harder for Trump: "... faithfully execute ..." There have been many times in Trump's life when he has said "I do" but then has not been entirely faithful. True, private infidelity does not always portend public faithlessness. But Trump's prior private infidelities are not confined to sex and marriage. Deep doubts exist about whether his word truly is his bond in dealing with creditors, investors, subcontractors, workers, business partners, customers — you name it. Thus far in life, he has had huge problems telling the truth and keeping his word.

Finally, here are the oath's most important words: "preserve, protect, and defend the Constitution." One cannot easily preserve, protect, and defend what one does not even understand, much less revere. Thus far, Trump has spent too little time reading, rereading and pondering this all-important document and its abiding principles. Let's hope it is not too late for him to become a true and faithful constitutionalist.

Akhil Reed Amar is the Sterling Professor of Law and Political Science at Yale University and the author of "The Constitution Today: Timeless Truths for the Issues of Our Era."