This week, Senator Rand Paul (R-KY) launched his bid for the GOP presidential nomination. A major part of his policy platform is to overhaul the U.S. tax code in a way that would have most taxpayers pay the exact same amount—what's referred to as a “flat tax.” Under his plan, this income tax rate would be 17 percent, which would be a tax cut for most taxpayers but an especially large one for the very richest Americans.

But seven years ago, in 2008, Rand Paul, then an advocate for Kentucky Taxpayers United, went much further during an appearance on local television show Kentucky Tonight, suggesting we lower the tax rate to a meager 10 percent. He justified this by citing historical church tithing rates of 10 percent.

HOST: What total percentage of income do you think should reasonably go to taxes—federal state and local—and what percentage of any do you think we should be able to keep for ourselves? PAUL: I'd like to chime in because I never heard a number there […] I'm going to say the church never asked for more than 10 percent. I think there's no reason we should have a higher than a 10 percent income tax federally and if we have to have an income tax. And I would say locally, we could have no income tax and about a 10 percent sales tax.

Watch it: