Former Rep. Adam Kinzinger (R-Ill.) bashed former President Trump online and said Christians who support him “don’t understand” their religion.

“I’m going to go out on a NOT limb here: this man is not a Christian,” Kinzinger said on X, formerly known as Twitter, responding to Trump’s Christmas post. “If you are a Christian who supports him you don’t understand your own religion.”

Kinzinger, one of Trump’s fiercest critics in the GOP, said in his post that “Trump is weak, meager, smelly, victim-ey, belly-achey, but he ain’t a Christian and he’s not ‘God’s man.’”