Rev. Dr. Joseph Lowery has been “fighting for rights for the powerless, giving a voice to the voiceless,” Rev. Al Sharpton said last night on Politics Nation. Sharpton interviewed Lowery, a civil rights leader who has come to be known as the dean of the Civil Rights movement. The 90-year-old icon said he supports the president’s gay marriage endorsement.

“I don’t think you can say we believe in equal rights for some people but not for others,” Rev. Lowery said. “I think that’s what we call an oxymoron. I think if you believe in equal rights, you have to grant them to all the people.”

The question of whether President Barack Obama’s endorsement of same sex marriage would hurt or aid in his fight for re-election has been gaining attention. The move was seen as a big risk to a primary base of his voters, many of whom are African-Americans, who support gay rights at a lower rate than that of whites.

WATCH REV. AL SHARPTON’S INTERVIEW WITH REV. DR. JOSEPH LOWERY

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When asked about the proudest moment of career, Rev. Lowery said it was giving the benediction of at Obama’s inauguration in 2009. “It was not only witnessing the inauguration of the first African-American president, but participating in it,” Rev. Lowery said.