REBECCA ROBERTS, host:
From NPR News, this is All Things Considered. I'm Rebecca Roberts.
Former President FRANKLIN ROOSEVELT: I, Franklin Delano Roosevelt, do solemnly swear...
Former President JOHN F. KENNEDY: I, John Fitzgerald Kennedy, do solemnly swear...
Former President RONALD REAGAN: I, Ronald Reagan, do solemnly swear...
Former President BILL CLINTON: I, William Jefferson Clinton, do solemnly swear...
ROBERTS: The Presidential Oath of Office - it's laid out in the Constitution. But did you know this? When Barack Obama takes it on Tuesday, he can choose not to swear, as NPR's Andrea Seabrook reports.
ANDREA SEABROOK: Article Two Section One of the Constitution actually reads like this.
Unidentified Man: Before he enter on the execution of his office, he shall take the following oath or affirmation. 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.
SEABROOK: Did you catch that? It was read here by an actor. It says, I do solemnly swear or affirm. The president has the option not to swear, but to affirm, instead. The root of this affirmation? Paul Lacey of the American Friends Service Committee says it comes from one of the basic tenets of the Religious Society of Friends, the Quakers.
Mr. PAUL LACEY (Clerk, American Friends Service Committee): The Quakers were among some of those groups that took very literally the injunction in Scripture in the Sermon on the Mount that you should swear not, just period. You swear not.
SEABROOK: Here's what the Bible says.
Unidentified Man: But I tell you, do not swear at all, either by heaven for it is God's throne or by the earth for it is his foot stool. Simply let your yes be yes and your no, no. Anything beyond this comes from the evil one.
Mr. LACEY: The meaning behind that for Quakers was not only the sense that if the Sermon on the Mount gives you an ethical principle, you ought to take it very, very seriously, but also that if you swear, you are suggesting that maybe other times you don't tell the truth.
SEABROOK: Still, affirming has been very, very rare. President Franklin Pierce chose to affirm his oath in 1853. But it's not just some antiquated relic of a bygone century either, says Paul Lacey. These days, secular humanists, atheists, and agnostics for whom swearing by God is actually against their consciences, as well as many religious conservatives and Quakers, choose to affirm in oath rather than swear it. Andrea Seabrook, NPR News.