The most prevalent claim I've heard is that the old testament covenant died with him on the cross and was replaced with the new covenant upon his resurrection. All without reference to scripture, of course. It does beg the question of whether people were allowed, or even able, to sin during the three days (yeah, right) he lay dead since there was no covenant in place for that time.
Thief and assassin for hire. Member in good standing of the Rogues Guild.