Watch President Obama’s Moving Rendition of “Amazing Grace”

Today, President Obama visited Charleston to give a eulogy for Reverend Clementa Pinckney, who was killed in the shooting last week along with eight other innocent victims. The speech lasted over half an hour, but it's the last two minutes that may be remembered forever. Obama broke into song, serenading the congregation and spectators with a heartfelt rendition of “Amazing Grace.” It didn’t take long for others to join in.

The significance of this moment can not be overstated. It features the nation's first African-American president singing a Christian spiritual written by a former slave trader in eulogy of a reverend shot in a church co-founded by a man who was part of a slave revolt plot.

The story of the song itself is one of transformation and is secure in its place as a talisman of the civil rights movement.

Civil rights activist and “Queen of Gospel” Mahalia Jackson once delivered a beautiful explanation of what the song meant to her. She said she sang the song ”to give magical protection – a charm to ward off danger, an incantation to the angels of heaven to descend ... I was not sure the magic worked outside the church walls ... in the open air of Mississippi. But I wasn't taking any chances.”