A decade and a half into the 21st century, the Voting Rights Act of 1965 is under fire, and white-on-black violence brings the cry that black lives matter. As we approach the 150th anniversary of the assassination of President Lincoln, we would do well to reconsider his most famous imperative: “with malice toward none; with charity for all.”

In his second inaugural address, delivered March 4, 1865, Lincoln declared that the fighting would last “until every drop of blood drawn with the lash, shall be paid by another drawn with the sword.” The war, he meant, would not end until slavery ended. Lincoln closed that address with the appeal for “malice toward none” and “charity for all,” exhorting his listeners to “strive on to finish the work we are in” and to “do all which may achieve and cherish a just and a lasting peace.”

Many at the time thought they knew what Lincoln meant, and many today understand those words in the same way: As the Union Army approached triumph, it seemed that Lincoln wanted the conquerors to treat their vanquished Confederates with mercy. But what if that reading misunderstands the fundamental political impulse behind those lyrical directives?

When the war ended little more than a month later, black and white Southerners harbored sharply clashing visions of the nation's future. African Americans envisioned the federal government enforcing freedom, equality and suffrage, and disenfranchising former Confederates. The defeated rebels, for their part, envisioned renewed black subordination and the restoration of their own rights, without federal interference.

Accordingly — despite emancipation and victory — African Americans looked ahead with trepidation. The day after the glorious fall of Richmond on April 3, 1865, Frederick Douglass warned a Boston audience that “hereafter, at the South, the negro will be looked upon with a fiercer and intenser hate than ever before.” When Robert E. Lee surrendered at Appomattox Court House in Virginia on April 9, the editors of the New York Anglo-African warned that there remained immense support for “oppressions akin to slavery.”

Two days after Lee's surrender, Lincoln addressed a crowd from the White House balcony, reflecting on the nation's reconstruction. He would “prefer,” he submitted, that voting rights be extended to black men who were “very intelligent” and to “those who serve our cause as soldiers.” His cautious suggestion irritated abolitionists. “Why can't he cut down the whole tree,” a white woman wrote in her Massachusetts diary, “instead of lopping off the branches?”

But the same suggestion struck Lincoln's antagonists as entirely too revolutionary. Among them was a young Shakespearean actor who stood in the crowd that evening. “That means nigger citizenship,” snapped John Wilkes Booth. “Now, by God, I'll put him through.” Three nights later, Booth entered the presidential box at Ford's Theatre and fired a single shot into the back of Lincoln's head.

The nation's first presidential assassination did not subdue former Confederates; many expressed glee and many continued to dream of retribution. As President Andrew Johnson sided with white Southerners, black Southerners just as rapidly reached for Lincoln's legacy and for the mandates of his second inaugural. They told Johnson, in petitions to the White House, that he was replacing “a man who had proved himself indeed our friend,” reminding him of the “liberty brought us and our wives and our little ones by your noble predecessor.”

Were these African Americans, and others who echoed their sentiments, ignoring Lincoln's recent call for “malice toward none” and “charity for all”? On the contrary, black mourners seem to have interpreted those words to apply, not to former Confederates, but just the opposite: to themselves.

That's why black mourners inscribed those phrases on the banner they carried through the nation's capital on the Fourth of July, 1865. That's why Douglass surmised that, had Lincoln lived, “the negro of the South would have more than a hope of enfranchisement and no rebels would hold the reins of Government in any one of the late rebellious states.” That's why Douglass concluded that “to the colored people,” Lincoln's death was “an unspeakable calamity.”

At the close of the second inaugural, Lincoln had added the imperative of working toward “a just and a lasting peace.” Douglass told his fellow mourners on July 4 that “permanent peace” could not be accomplished without justice, and justice required going beyond legal freedom, to encompass voting rights. “Slavery,” he believed, “is not abolished until the black man has the ballot.” That's what Lincoln meant too, apparent in his call for the first steps toward black suffrage that was offered in the White House speech that Booth's bullet transformed into his last public address.

Or at least that was the case made by African American victors-turned-mourners, when they looked to the spirit of the slain president to realize their visions of freedom and equality. Lincoln's call to “strive on to finish the work we are in” today holds a special poignancy — and a call to action. For as protesters in New York, Florida and Missouri remind us now, without justice, peace will remain elusive. As will Lincoln's spirit of “malice toward none” and his guiding vision of “charity for all.”