Khan added, “You have sacrificed nothing and no one."
In an interview with ABC News' George Stephanopoulos, Trump replied that he has "made a lot of sacrifices" by creating "tens of thousands of jobs."
>> A Muslim American challenges Trump
Trump then took aim at Khan's wife, saying, "She had nothing to say. She probably, maybe she wasn’t allowed to have anything to say. You tell me. But a plenty of people have written that. She was extremely quiet, and it looked like she had nothing to say. A lot of people have said that.”
>> Watch the clip here
Both Democrats and Republicans condemned Trump's statements Saturday.
"He attacked the distinguished father of a soldier who sacrificed himself for his unit, Captain Khan," said Democratic presidential nominee Hillary Clinton. "I think it is fair to say he is temperamentally unfit and unqualified."
Democratic vice presidential nominee Tim Kaine added, "If you don't have any more sense of empathy than that, then I'm not sure you can learn it."
Ohio Gov. John Kasich, who ran against Trump in the Republican primary, tweeted, "There's only one way to talk about Gold Star parents: with honor and respect. Capt. Khan is a hero. Together, we should pray for his family."
>> See Kasich's tweet here
Late Saturday, Trump's campaign issued a statement called "Setting the record straight":
"While I feel deeply for the loss of his son, Mr. Khan who has never met me, has no right to stand in front of millions of people and claim I have never read the Constitution, (which is false) and say many other inaccurate things," the statement read. "If I become President, I will make America safe again."
>> Read the full statement here
But Khan wasn't buying it.
"This is faked empathy," Khan said, according to the Washington Post.
"What he said originally – that defines him. ... People are upset with him. He realizes, and his advisers feel that was a stupid mistake. That proves that this person is void of empathy. He is unfit for the stewardship of this great country. You think he will empathize with this country, with the suffering of this country’s poor people? He showed his true colors when he disrespected this country’s most honorable mother ... all the snake oil he is selling, and my patriotic, decent Americans are falling for that. Republicans are falling for that. And I can only appeal to them. Reconsider. Repudiate. It’s a moral obligation. A person void of empathy for the people he wishes to lead cannot be trusted with that leadership. To vote is a trust. And it cannot be placed in wrong hands.”
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He added that his wife didn't speak at the convention because "she was just totally emotionally spent," and that Trump's remarks about her are "typical of a person without a soul."
Khan also asked Senate Majority Leader Mitch McConnell, R-Ky., and House Speaker Paul Ryan, R-Wis., to stand up to Trump.
“I am saying to them that this is your moral duty — and history will judge you," Khan said.
"This will be a burden on their conscience for the rest of their lives."