As America is celebrating the Reverend Doctor Martin Luther King Jr’s birthday, it’s fitting to mount a defense against those using him as a political weapon, to carry on the legacy of his words, “Hate cannot drive out hate; only love can do that.”

Secular culture chooses to focus on King’s title of “doctor,” but it was from his faith in Christ that he drew his moral authority, not his doctorate in systematic theology. One passage he cited often came not from a textbook but from the Book of Matthew.

“I tell you, ‘Love your enemies and pray for those who persecute you,’” the apostle quotes Christ as saying, “‘that you may be children of your Father in heaven.’” Calvin Trillin of the New Yorker heard King demonstrate this to a man who questioned him on a flight. “I think love is the most durable element in the world,” King said, “and my whole approach is based on that. 

It’s easier to love those who look, think, and tweet like us, but King saw he couldn’t reach the mountaintop without converts. So, he followed the rhetorical advice of another martyred American, President Lincoln: “Do I not destroy my enemy when I make him my friend?”

“It would be nonsense to urge men to love their oppressors in an affectionate sense,” King said in a 1957 speech. “The Greek language comes to our aid in dealing with this problem,” citing the three words Ancient Greeks used for love in the Bible. First came eros, which “represented the yearning of the soul for the realm of the gods.” Second was philia, an “intimate affection between personal friends,” transactional love. 

“When we speak of loving those who would oppose us,” King said, “we refer neither to eros nor philia. We speak of a love which is expressed in the Greek word agape ... understanding, creative, redeeming goodwill for all men.”

I always tremble a bit hearing King describe this transcendent love; I recall my Yiayia Argyro, referring to me as, “Agape mou,” or “my beloved.” If you are fortunate enough to have a grandmother who loves you without conditions, you have experienced agape.

“It is the love of God operating in the human heart,” King said. “When we rise to love on the agape level, we love men not because we like them, not because their attitudes and ways appeal to us, but we love them because God loves them. Here we rise to the position of loving the person who does the evil deed while hating the deed that the person does.”

Agape inspired the primate of the Greek Orthodox Archdiocese, Archbishop Iakovos, to march at Selma. Iakovos said that, like my grandparents, he came from Turkey, where he was “a third-category citizen” as a Christian, and joined King — as seen on the cover of Life magazine — “to take revenge against all those who oppress people.” 

I interviewed a University of North Carolina professor of African, African American, and Diaspora Studies, Claude A. Clegg III, about his book, “The Black President: Hope and Fury in the Age of Obama,” and asked him to reflect on King’s embrace of Ancient Greek concepts.

“What perhaps sets King apart most from his contemporaries,” Dr. Clegg wrote, “is his purposeful injection of the Christian ethic of love, particularly the agape variety, into the civil rights movement. Beyond simply calling for nonviolent resistance to oppression, King offered a moral clarity that positioned the movement as ultimately resting on the capacity of both the oppressed and the oppressor to bridge their differences as human beings.” 

King repeated this message many times, saying nonviolence “does not seek to defeat or humiliate the opponent, but to win his friendship and understanding” because “agape makes no distinction between friends and enemy; it is directed toward both.” 

“King was appealing to a higher love,” Dr. Clegg wrote, “a new model of human relations that set aside individual particularisms in favor of a common, universally cherished humanity.” As America celebrates King’s birth, it’s a chance to be inspired by his faith — and to prove him right that love is the most durable element of all.