Notre Dame decries Lou Holtz's RNC speech saying Biden is 'Catholic in name only' for his abortion views. So Holtz doubles down.

Legendary former Notre Dame football coach Lou Holtz delivered a speech to the 2020 Republican Nation Convention on Wednesday in which he praised President Donald Trump, proclaimed the greatness of the United States, reminded viewers why they should take pride in being Americans, and ripped Democratic nominee Joe Biden's campaign for its pro-abortion stance.

Holtz declared that pro-abortion Catholic politicians — which would include Biden — are "Catholic in name only."

On Thursday, Notre Dame attempted to distance the school from the coach's remarks about a fellow Catholic, and Biden called criticism of his faith "preposterous."

But Holtz was not deterred, and the next day, he doubled down on his assertion during an interview on Fox News.

What did he say?

As Holtz delineated his reasons for supporting Trump, he noted that one of the reasons he, as a Catholic, backs Trump is because "nobody has been a stronger advocate for the unborn than President Trump."

And that stands in stark contrast to the pro-abortion political and policy stances of the Biden campaign, despite Biden's repeated reminders to voters that he's a practicing Catholic and has been one his whole life.

"The Biden-Harris ticket is the most radically pro-abortion campaign in history," Holtz said. "They and other politicians are Catholic in name only and abandoned innocent lives."

WATCH: Lou Holtz's full speech at the Republican National Convention | 2020 RNC Night 3www.youtube.com

What Notre Dame and Biden say?

The day after Holtz's speech, Notre Dame President Rev. John Jenkins put out a statement trying to put as much distance as possible between the school and the pro-life, pro-Trump coach:

While Coach Lou Holtz is a former coach at Notre Dame, his use of the University's name at the Republican National Convention must not be taken to imply that the University endorses his views, any candidate or any political party. Moreover, we Catholics should remind ourselves that while we may judge the objective moral quality of another's actions, we must never question the sincerity of another's faith, which is due to the mysterious working of grace in that person's heart. In this fractious time, let us remember that our highest calling is to love.

MSNBC's Andrea Mitchell asked Biden, who has reportedly been denied communion over his pro-abortion views, about Holtz's and others' attacks on his faith, which the former vice president called "preposterous."

"Look, I'm not going to proselytize," Biden told Mitchell. "I'm a practicing Catholic. I've been a practicing Catholic my whole life. I practice all the elements of my faith."

Holtz doubles down

But Holtz was not to be deterred from his message.

On Friday, he appeared on Fox News' "Bill Hemmer Reports" to discuss his remarks and the school's response, and he made it clear that he stood by every word.

"People have taught me that to murder an unborn child at nine months is illegal," Holtz told host Bill Hemmer. "That's not part of the Catholic faith. And Joe Biden — he may be a wonderful individual, I hear great things about him — I'm not casting aspersions on his character, his integrity, but I am casting aspersions on his decision."

"When he said that you can abort a baby at the nine month of pregnancy, and that's perfectly all right?" Holtz asked Hemmer. "No, by the way I was taught, the Catholic Church, that's not all right and I'm going to speak up about it.

"I'm not criticizing him. I'm not passing judgment. But that's wrong," he said.

Holtz said that though the school is welcome to say what they want, he disagreed with Jenkins' implication that Holtz questioned the sincerity of Biden's faith.

"I did not question his sincerity, Bill, but I do question the judgment he makes," Holtz said. "When you come out and say a baby can be aborted nine months into pregnancy, I can't agree with that.

"I feel strongly about it, but that's because of the way I was raised in the Catholic faith," he continued, noting the church's teaching that "when selecting a president ... you should first of all look at how they feel about abortion" and vote for the person who opposes abortion.

"If you want me to say killing babies is OK, no, I cannot say that," Holtz said, adding that he has a problem with people who would try to silence him.

"I'm not passing judgment on anybody's character, integrity ... what I'm saying is, 'If you're pro-abortion, I'm opposed to you.' I'm allowed to have my opinion, and don't try to silence me," he concluded.