Wonder performed three songs, including Shelter in the Rain, for the hundreds of mourners who gathered at Greater Bethany Community Church to remember James, who died from complications of leukemia on January 20 at the age of 73.
Aguilera performed At Last and introduced her tribute by saying, "Out of all the singers that I've ever heard, she was the one that cut right to my soul and spoke to me. So tonight, Etta, this song is for you."
Civil rights leader Reverend Al Sharpton delivered the eulogy, detailing James' rise from poverty and hailing the singer as a "bridge of American culture that changed the culture of the world".
Sharpton also read aloud a statement from President Barack Obama, who said, "Etta will be remembered for her legendary voice and her contributions to our nation's musical heritage."