The Republican and Democratic leaders of both chambers of Congress held hands and swayed Tuesday in the Capitol as the U.S. Army chorus sang “We Shall Overcome.”

Such rare harmony came in honoring the Rev. Martin Luther King Jr. and his wife, Coretta Scott King, with the Congressional Gold Medal and celebrating the 50th anniversary of the Civil Rights Act of 1964. It was far from the scene of the bitter Senate debate of five decades ago, and the controversies of today crept into Democrats’ remarks promoting a new voting rights bill.

But House Speaker John Boehner, R-Ohio; Senate Majority Leader Harry Reid, D-Nev.; House Minority Leader Nancy Pelosi, D-Calif.; and Senate Minority Leader Mitch McConnell, R-Ky. could agree on the enormousness of the Kings’ accomplishments and the hard-fought law banning discrimination in public facilities.

Boehner said the law “may be the most fundamental and consequential legislation of our long history.”

U.S. Rep. John Lewis, an Atlanta Democrat who was a compatriot of the Kings’, called them “one of the most distinguished and admired husband and wife teams of the 20th century.”

Lewis added, “When they stood together, their bodies became great pillars of hope, the American house resting on their shoulders.”

Several members of the King family were on hand for the presentation of the award, which will be housed in the Smithsonian’s National Museum of African American History and Culture.

Congress’ leaders also lauded President Lyndon B. Johnson; U.S. Sen. Everett Dirksen, R-Ill.; and others who helped shape and push the Civil Rights Act. The Senate debate — which included epic filibusters against the bill by Southern Democrats such as U.S. Sen. Richard Russell of Georgia — provoked awe in a young McConnell as the act finally passed.

“It was a powerful lesson in how determined men and women can use the Senate to achieve our founding purposes,” McConnell said.

Several Democrats took the opportunity to urge movement on an update to the Voting Rights Act that would require federal approval for any voting law changes in Georgia and three other states. The bill is a response to a U.S. Supreme Court decision last year that effectively ended the practice of “pre-clearance.”

The Democratic-led U.S. Senate will hold a hearing on the bill Wednesday, but the Republican-run House has given no indication that it will move the bill. GOP leaders in Georgia and elsewhere have said pre-clearance is burdensome and unnecessary because anyone can sue to block a discriminatory voting practice.

Lewis also honored a more solemn 50th anniversary Tuesday: the June 1964 murders of James Chaney, Andrew Goodman and Michael Schwerner in Mississippi during the Freedom Summer.

Chaney was a black Mississippian, while Goodman and Schwerner were Jewish New Yorkers. They were investigating the burning of a black church and registering voters.

“These three young men – Jewish, African-American – didn’t die in Vietnam,” Lewis said. “They died right here in our own country trying to encourage people to become participants in the democratic process.”