Presidential hopeful (or hopeless) Jeb Bush has said that the only vetting process America should need with incoming Syrian refugees is to check whether or not they are Christians. If they celebrate Christmas, let them in; if they celebrate Ramadan, keep them out.

Bush’s clever little idea ran into a major roadblock when journalists asked him how, exactly, he expected officials to screen refugees for their religious beliefs.

“Well, you’re a Christian, I mean, you can prove you’re a Christian,” Bush responded.

“How?” a reporter asked.

“I think you can prove it,” Bush said. “If you can’t prove it, you know, you err on the side of caution.”

Apparently Bush believes that Christians can recognize their own kind on sight. A Christ-dar, if you will.

Watch Bush’s blunder here: