By Andrew Kaczynski and Chris Massie, CNN

(CNN) -- President Donald Trump's nominee for a federal judgeship in Texas invoked religious crackdowns by the Nazis in Germany and other totalitarian regimes to describe the treatment of Christians in the US during three interviews in 2013 and 2014.

Jeff Mateer, who currently serves as the first assistant attorney general of Texas, is nominated for a lifetime appointment on the US District Court for the Eastern District of Texas.

LGBT rights groups and Democratic senators have raised concerns over comments from Mateer, first published by CNN's KFile, in which he described transgender children as evidence of "Satan's plan," lamented that states were banning conversion therapy, and argued that sanctioning same-sex marriage would lead to polygamy and bestiality.

Mateer made his comments about the treatment of Christians in the US in three separate interviews on "Chosen Generation with Pastor Greg," a radio show hosted by Pastor Greg Young that, according to its website, is "an informational program that will give you the information you need to argue for a biblical worldview, a Constitutional Republic and the truth to refute all of the lies and disinformation from media to academia to what has become of the church itself."

At the time of the interviews, Mateer was general counsel for the First Liberty Institute, a nonprofit religious liberty advocacy group known before 2016 as the Liberty Institute. In one of his radio broadcasts, Young said the institute had a weekly segment on his show to update his audience on issues surrounding religious freedoms.

Representatives for the White House, the Justice Department and the Texas attorney general's office did not respond to multiple requests for comment for this story.

Mateer, in an appearance with Young in October 2014, compared actions taken by Houston Mayor Annise Parker to that of the Nazis and other totalitarian governments. Houston city officials had issued subpoenas for sermons delivered by pastors who opposed an LGBT anti-discrimination ordinance (Parker later withdrew the subpoenas following an outcry over the city's actions).

"You know the proof in the pudding is, as my 99-year-old grandmother would say, is look what they do they get in, and the first thing they want to do is they go after the pastors, they go after their sermons," Mateer said. "And I was asked last week, 'pastor,' I was asked why by a person, 'Well isn't that unprecedented?' And I said, and I kind of took them back, and I said, 'No it's not unprecedented,' and they're like 'really?,' thinking, 'well it's happened in American history.' No, I don't really have an instance from American history. But I do know it happened in the 1930s and 1940s in Nazi Germany. It happened in Stalinist Russia, and it happened in Maoist China. Totalitarian governments often want to censor and silence pastors, and that's exactly what the mayor of Houston, she's in that company, when she makes this type of affront on religious liberty."

In another appearance in November 2013, Mateer and host Greg Young discussed a case before the Supreme Court that dealt with the constitutionality of a New York town's council meetings opening with public prayer. The court ultimately ruled that the prayers did not violate the Constitution.

Young said to Mateer, "As you said Jeff, I think this whole idea, but what are we watching -- there's film, you can find old black and white film footage of Hitler's organizations and of the Communist regime going in and doing exactly what you're talking about, which is ripping up and destroying all Christian symbolism within the country. It's a pretty serious situation."

Mateer responded, saying, "No you're right, and I truly believe because we know, history teaches this, totalitarian governments, what they first attack is freedom of religion, freedom of beliefs. Because they know that strikes at the core of freedom. If they can destroy freedom of conscience, then every other liberty is at stake. And so, we see that in history, whether that be Nazi Germany, or Communist Russia, or Communist China. That's what they strike at first. And it's just a stepping stone to taking away all freedom."

In exchange in late 2013, Mateer compared Obama administration policies related to Obamacare to Nazi-era policy. Mateer was discussing the Hobby Lobby Supreme Court case that challenged Obamacare's contraceptive mandate.

Young told Mateer that the administration's approach looks like "what happened in the 1930s in Germany with Hitler and his socialist party" when the Nazis told Jewish people they couldn't practice their religion and remain in business.

Mateer responded that the Obama administration made a calculated decision to change references from 'freedom of religion' to 'freedom of worship.'

"We're starting to see that, because in making these arguments, 'Oh you can believe whatever you want to believe. You can believe, as a believer, that abortion is wrong. Just don't do anything that puts that into practice. Don't do anything that takes your beliefs outside the four walls of your church,'" Mateer said. "I think, yes, making a parallel to, we've seen this in history before, when totalitarian governments want to suppress, they go after people of faith, they go after religious beliefs, because if you take away religious beliefs, you really are going to take, all the other freedoms are hinged off of religious beliefs and your freedom of religion. When you start taking that away, what's in jeopardy, our political freedoms and every economic freedoms, every other freedom. We see that in totalitarian governments. What they want to do is take away the ability to practice your religion."

Young responded that the left was trying to suppress history that would illustrate modern-day comparisons to Nazi Germany.

"I think you're correct in that," Mateer responded.

Mateer added that the Obamacare contraceptive mandate fight woke up the Catholic Church to religious liberty issues. Mateer then recited German Lutheran pastor Martin Niemöller's famous quote about the Holocaust.

"Now they, in waking up the Catholic Church, they woke up a sleeping giant, who really, you think about it, the last decade, we've not seen the Catholic Church that engaged on religious liberty issues, until this issue," Matter said. "But I think what happens is that when it starts to hit you and it hits your church, you start realizing, 'Oh my, that they come after us.' Of course there's that great quote that comes out of the Nazi Germany, 'First they came for what, the communist, and then they came for the Jews, and then eventually they came for me,' the Niemöller quote. I think when people start realizing, 'Oh, they are coming after me,' they wake up."

"It's time for people of faith to realize, yes, this administration, this government is coming after you," Mateer continued. "They want to limit your religious liberty rights. They want to put them in a box. They want you to keep them in your church. They don't want you to go outside. Like the Catholic Church, it's time for the evangelicals and others of faith to wake up."