Progressive faith leader Jim Wallis decried Republican presidential candidate Donald Trump’s recent campaign rhetoric and affirmed his belief that “racism is in the air we breathe” during a recent appearance on The Church Boys podcast.

Wallis, who released his new book, “America’s Original Sin: Racism, White Privilege, and the Bridge to a New America,” on Jan. 19, specifically addressed the “racial fear” that he believes Trump is spawning as he competes for the GOP nomination.

“When Donald Trump deliberately is fueling racial fear — and even racial hate — it really poisons and pollutes the political landscape of America,” Wallis said during the wide-ranging interview. “Racism is in the air we breathe. It’s everywhere, and we’re all relating to it all the time, so when there are these appeals that I think are based on fear and hate, it really poisons that atmosphere.”

The preacher, who is known for taking progressive stances on a variety of issues, said that he believes that racism is “a gospel” issue — one that Christians must come together to confront.

“I’m challenging Donald Trump’s language on race, because, for me, that’s a gospel issue,” Wallis said, adding, “I don’t want the hat that says, ‘Make America Great Again’ to really mean, ‘Make America White Again.’ That’s really not what it ought to be.”

Listen to the interview at the 53:00 mark below:

In “America’s Original Sin,” Wallis discusses “the state of race in America,” acknowledging in the podcast interview that he knows how difficult the subject can be to navigate, though he repeatedly implored Christians to see race “as a faith issue, not just a political matter.”

“America’s original sin of slavery and racism is still with us,” he told The Church Boys. “It still lingers in so many of our systems and our culture.”

Wallis also discussed the idea of “white privilege,” expressing his believe that, if a white teenager like his own son had been walking in the same place in Sanford, Florida, and at the same time of night when Trayvon Martin was killed, he or she would have returned home safely without incident.

“White privilege is something we don’t often even recognize … the normality of whiteness, the rightness of whiteness,” he said. “All of us have succeeded because of hard work … but if we’re not aware that we have had an easier time even in our success because we’re white than if we we’re people of color we’re just not recognizing the reality around us.”