Spicer also engaged in a discussion on what the Republican Party would do if Trump stepped down as the Republican nominee. He said during a radio interview
with former baseball player Curt Schilling Trump would need to understand the "severity" of his comments.
Schilling, the former baseball star and prominent conservative, said Trump's comments made the election "unwinnable" for the Republican nominee.
"I think, look, as Christians and Americans, we all understand that people make mistakes and ask for forgiveness. How they do it and how they take a situation and show that they want to change and be better is really kind of sometimes the bigger part of a problem or an issue. How he handles this over the next 24 hours is absolutely critical."
"If you don't get the severity of this, then that will speak very loudly," Spicer added, after repeating Trump would need to ask for forgiveness.
Trump apologized for his comments in a video statement released after midnight on Saturday, though he immediately pivoted to attack the Clintons.
"I said it. I was wrong. And I apologize," Trump said.
The RNC chief strategist added the comments could not be defended in anyway.
"No, absolutely not and that's why I'm saying there is no defending it," Spicer said. "There is no excusing it. Whether you have a daughter or a sister or a mom, I mean, you look and you go that is not how you describe a woman. No way, no how, ever."
Spicer said people of faith should recognize people make mistakes. Schilling asked Spicer what would happen if Trump were to step down as the Republican nominee.
"I'm not a big fan of hypotheticals, but the answer is we'd have to cross that bridge when we come to it," Spicer said. "If he -- and frankly that holds true with any office -- if there's a vacancy, then it depends on state law. We have never had that happen before, at least in modern times that I'm aware of."
Spicer cited the case of Mel Carnahan in Missouri, who died in a plane crash weeks before the 2000 Senate election, as precedent for how to change names on the ballot.
"We don't have that scenario right now. I think what we have to do, to your point, recognize that there's still a choice," said Spicer. "Donald Trump made some comments 11 years ago that weren't appropriate. He has apologized. I think we will see in the next 20, 48 hours how he continues to hold and handle this."
He added voters would have decided if Trump's 2005 comments outweighed the decisions Hillary Clinton would make as president.
"But we also do have a choice and have to recognize that Hillary Clinton will have spending, appointments, decisions and priorities that could vastly change our country," he added. "We have to make a decision whether someone's comments 11 years ago outweigh the decisions that a president Hillary Clinton would make in terms where we are as a country now and what those decisions would have on the coming generation."
He added while he found Trump's comments were "reprehensible," he believed Clinton's actions as secretary of state were worse.