Jesus claimed, by implication, that these "stories" were literal accounts in reference to creation, Adam and Eve, Abel, Noah and the flood, Abraham, David, Solomon, etc. As well He made more general statements about the Bible's veracity such as, "the Scriptures cannot be broken", etc. If Jesus Christ is indeed God, as He claimed, the Savior of sinners, He would know whether those accounts were true or simply parables; and since He claimed they were true they must be, or it would refute His integrity or omniscience and thus His Deity and His ability to save a sinner.