Story highlights "I will consider it a personal insult -- an insult to my legacy -- if this community lets down its guard," Obama said

Hillary Clinton lauded Obama and directly took on the birther controversy

Washington (CNN) President Barack Obama delivered an impassioned plea to the African-American community Saturday night to help stop Donald Trump, saying he would consider it a "personal insult" to his legacy if black voters didn't turn out for Hillary Clinton.

Addressing the Congressional Black Caucus gala for the last time as president, Obama warned that while his name would not be on the ballot in November, all of the progress that the country has made over the last eight years was on the line.

"If I hear anybody saying their vote does not matter, that it doesn't matter who we elect -- read up on your history. It matters. We've got to get people to vote," Obama said. "I will consider it a personal insult -- an insult to my legacy -- if this community lets down its guard and fails to activate itself in this election. You want to give me a good sendoff? Go vote."

Obama's speech -- coming less than two months away from Election Day -- marked some of his harshest words yet about Trump, as well as his most forceful call on the black community to get behind Clinton.

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