Rick Warren, who had been expected to explain contradicting statements about gay marriage today on ABC's This Week, backed out at the last minute because he was “sick with exhaustion,” Politico reports. The prominent evangelical pastor was to clarify the difference between his claims last week that he "never once gave an endorsement" to California's Prop 8 and a YouTube video in which he says, "If you believe what the Bible says about marriage, you need to support Proposition 8." (More Rick Warren stories.)