Harold Camping says "when it comes to trying to recognize the truth of prophecy, we're finding that it is very very difficult," a point he, so far as I can find, never made in any of his extensive, definitive exegeses of prophecy, a qualification and a caution he never offered when people sent him money, sold everything, and staked their hope on the parousia Camping said was certain. Further, Camping notes, "Sometimes [God] gives us the truth and sometimes He gives us something that causes us to wait further upon Him."
This isn't just not an apology, it's a statement that, in a very real way, it's not even possible for Camping to have been wrong. He is, in a sense, hermetically sealed against error, since even when he was wrong, that too was from God. God gives truth, which Camping relays, and God gives lies, which Camping also relays. But they aren't lies, exactly, but a method of teaching God uses.
Read the rest of the essay @ Religion Dispatches.