Sen. Mitt Romney (R-Utah) was the lone Republican vote to convict President Trump of abuse of power on Wednesday, and Stephen Colbert thanked him generously on The Late Show , whether Romney wanted the praise or not.Colbert began by ruing Trump's impeachment acquittal and "the new normal" it creates that "asking a foreign power to interfere in our election" is just fine. And he shook his head at the Senate Republicans claiming "they're not setting the precedent that presidents are above the law because Trump is going to change," especially Susan Collins (R-Maine), "the senator who has most successfully talked herself into believing she believes in something."Still, "on this dark day, there is someone I would like to thank for giving me a ray of hope," Colbert said, playing extended parts of Romney's Senate speech, in which he explained his vote to convict in terms of his faith and fealty to the oath he took to render impartial justice."You know, in my own small way I try to live my faith, and over the years, I've made a lot of fun of Mitt Romney," Colbert said, recapping some of the punchlines. "And I mean this sincerely: After seeing that speech, I would do all those jokes again, because that's the oath I took. But I do want to say, that was an inspiring speech. Because hearing Mitt Romney taking his oath to God seriously was like finding water in the desert." He explained how "we know Republicans are lying when they say that Trump didn't do anything wrong" and should remain in office, then how their votes to acquit condemn them: "Oaths may not mean a lot to some people. But here's what it's about: When you take an oath, you can't think one thing and say another. You are asking God to witness, on the pain of your immortal soul, that what you whisper in your heart is what comes out of your mouth." He quoted Thomas Moore in the play A Man for All Seasons, equating Trump with Henry VIII."So join me in thanking Mitt Romney for being honest, for not lying to us or to himself, for serving the Constitution rather than that monstrous child in the White House ," Colbert said. "Why can't he be president? Thanks, Obama." Watch below.