The Collaborative International Dictionary of English v.0.48:

demythologize \demythologize\ v. t.
   to remove the mythical elements from; -- of writings, such as
   the Bible.
   [WordNet 1.5]

WordNet (r) 3.0 (2006):

demythologize
    v 1: remove the mythical element from (writings); "the Bible
         should be demythologized and examined for its historical
         value" [syn: demythologize, demythologise] [ant:
         mythicise, mythicize, mythologise, mythologize]

Moby Thesaurus II by Grady Ward, 1.0:

35 Moby Thesaurus words for "demythologize":
   account for, allegorize, clarify, clear up, crack, decipher,
   demonstrate, elucidate, enlighten, euhemerize, exemplify, explain,
   explain away, explicate, exposit, expound, give reason for,
   give the meaning, illuminate, illustrate, make clear, make plain,
   popularize, rationalize, shed light upon, show, show how,
   show the way, simplify, solve, spell out, throw light upon, unfold,
   unlock, unravel