50 years ago, King promotes voting rights — and coins a phrase

Fifty years ago Wednesday, Martin Luther King, Jr., marked a milestone in voting rights -- and stamped a phrase onto the political lexicon.

"The arc of the moral universe is long, but it bends toward justice," King told supporters during a speech in Montgomery, Ala., on March 25, 1965, capping the historic voting march that had begun four days earlier in Selma.

Many a candidate and lawmaker have echoed that statement in the half-century since, including the nation's first African-American president.

In August 2013, paying tribute to King's "I Have A Dream" speech, President Obama said: "The arc of the moral universe may bend towards justice, but it doesn't bend on its own. "

Later that year, in his statement on the death of Nelson Mandela, Obama said the South African leader "bent the arc of the moral universe towards justice."

King's phrase came in the speech that capped one of the pivotal moments of the civil rights era: The Selma-to- Montgomery march for voting rights. That campaign had begun weeks earlier with the beating of marchers on the Edmund Pettus Bridge in Selma. Obama and others recently commemorated the 50th anniversary of that "Bloody Sunday."

Back in 1965, demonstrators marched in support of what became the federal Voting Rights Act, the law that transformed American politics right through to Obama's two elections and the run-up to the 2016 presidential contest.

Millions more African-Americans joined the voting rolls -- and many got elected to office -- in the wake of the Voting Rights Act of 1965. The movement that pushed for it inspired women, gays, Hispanics and other groups to demand their rights as well.

King's speech in Montgomery, delivered within earshot of the office of segregationist Gov. George Wallace, is also known as the "How long? Not long" address.

The civil rights leader used that incantation to argue that black Americans would overcome the legacy of segregation, including barriers to voting. (The speech is also memorialized in the final scene in the film "Selma.")

"I come to say to you this afternoon, however difficult the moment ... however frustrating the hour ... it will not be long," King said that day. "Because truth crushed to earth will rise again.

"How long? Not long! ... because no lie can live forever!"

Then, later:  "How long? Not long! Because the arc of the moral universe is long, but it bends toward justice. "

King adopted that line from a 19th century abolitionist named Theodore Parker, who used similar language to predict the demise of slavery.

Wrote Parker in a sermon: "I do not pretend to understand the moral universe, the arc is a long one, my eye reaches but little ways. I cannot calculate the curve and complete the figure by the experience of sight; I can divine it by conscience. But from what I see I am sure it bends towards justice."

King's formulation has inspired any number of advocates in the past 50 years, from women's and gay rights to the fight against religious extremism.

And it did not take long for King's proclamation to become reality in at least one respect: President Lyndon Johnson signed the Voting Rights Act less than five months after that speech in Montgomery.