Speaking from the pulpit of the church that Martin Luther King Jr once led, Mr Obama did not mention President Donald Trump.
But the first black president drew unmistakable contrasts with his successor, and he implicitly lambasted how Mr Trump has handled voting procedures and ongoing civil unrest amid a national reckoning over systemic racism.
Mr Obama called on Congress to renew the Voting Rights Act, which Mr Trump and Republican congressional leaders have left unchanged since the Supreme Court diminished the landmark law in 2012.
“You want to honour John? Let’s honour him by revitalising the law that he was willing to die for,” Mr Obama said, arguing that the bipartisan praise for the Georgia congressman since his death is not enough.
Mr Obama endorsed ending the Senate filibuster if that is what is needed to pass an overhauled voting law.
He called the procedural hurdle that effectively requires 60 votes to pass major legislation a Jim Crow relic, referring to the segregation era.
The Democratic-led House has adopted a sweeping rewrite of the Voting Rights Act, now named after Mr Lewis.
It faces opposition in the Republican-led Senate and likely could not get 60 votes even if Democrats reclaim a narrow majority after the November elections.
Specifically, Mr Obama called for all Americans being registered to vote automatically, restoring voting rights to felons who have completed their sentences, expanding early voting, ending partisan gerrymandering of districts and making election day a national holiday.
Mr Obama noted that the original Voting Rights Act of 1965 and its renewals drew Republican and Democratic votes in Congress and were signed by presidents from both parties.
Mr Obama singled out former president George W. Bush, a Republican, who also spoke Thursday at Ebenezer Baptist Church near central Atlanta.
Still, Mr Obama said: “There are those in power doing their darnedest to discourage people from voting by closing polling locations and targeting minorities and students with restrictive ID laws … even undermining the Postal Service in an election that’s going to be dependent on mail-in ballots.”
Hours before Mr Lewis’ funeral, Mr Trump suggested delaying the November election, something he doesn’t have the authority to do.
Mr Trump has falsely claimed that a surge of mail ballots because of the coronavirus pandemic will threaten the election’s legitimacy.
Mr Trump has opposed moves in Congress to help the financially struggling US Postal Service handle the sharp upsurge in mail voting.
Mr Obama compared current national circumstances to the earlier civil rights era when Mr Lewis helped lead the Student Nonviolent Coordinating Committee and became an understudy to Mr King.
Bull Connor may be gone, but today we witness with our own eyes police officers kneeling on the necks of black Americans
“Bull Connor may be gone, but today we witness with our own eyes police officers kneeling on the necks of black Americans,” Mr Obama said, alluding to the May 25 killing of George Floyd by a white Minneapolis police officer.
“George Wallace may be gone, but we can witness our federal government sending agents to use tear gas and batons against peaceful demonstrators.”
Mr Connor was the Birmingham, Alabama, police commissioner who ordered the use of police dogs and fire hoses against civil rights demonstrators.
Mr Wallace, the four-term governor of Mr Lewis’ native Alabama, built his political career on a defence of segregation and overt appeals to white grievances, and it was his state highway patrol who beat Mr Lewis and others as they marched for voting rights in 1965.
Mr Trump, like Mr Wallace in his multiple presidential bids, is campaigning as a “law and order” figure.
The president frames protesters who have gathered across the country since Mr Floyd’s killing as anarchists who threaten the nation’s stability, especially in suburbs, and he has dispatched federal authorities to some cities over the objections of local authorities.
Mr Lewis, who died July 17 at the age of 80, was one of the original Freedom Riders, activists who challenged segregation on commercial bus lines in the Deep South during the early 1960s.
He was the youngest speaker at the 1963 March on Washington, where Mr King delivered his I Have A Dream speech.
Bloody Sunday and the voting rights marches occurred two years later, months before president Lyndon Johnson signing the Voting Rights Act.
Mr Obama awarded Mr Lewis the Medal of Freedom in 2011.
Mr Trump was the only living president who played no official role in a week of public remembrances for Mr Lewis.
Besides Mr Obama and Mr Bush, former president Bill Clinton spoke at Ebenezer Baptist Church.
Former president Jimmy Carter, who is 95, sent a statement read by the church’s senior pastor, the Reverend Raphael Warnock.
Mr Lewis had called Mr Trump an illegitimate president ahead of his 2017 inauguration and chided him for stoking racial divisions.
Mr Trump answered by calling Mr Lewis “all talk, talk, talk (and) no action” and describing his Atlanta congressional district as “crime infested”.
Mr Obama exalted Mr Lewis as a “founding father” of a “better America”.
“Someday, when we do finish that long journey towards freedom, when we do form a more perfect union – whether it’s years from now or decades or even if it takes another two centuries,” he said.
“John Lewis will be a founding father of that fuller, fairer, better America.”
