Originally Posted by epignosis
The simple answer to this is, that God can then give this meaning to the ones he wants. In other words it is hidden to the ones not deserving. Also it can be given at the correct time.
Mark 4:11 (King James Version)
11And he said unto them, Unto you it is given to know the mystery of the kingdom of God: but unto them that are without, all these things are done in parables:
Matthew 13:11-13 (King James Version)
11He answered and said unto them, Because it is given unto you to know the mysteries of the kingdom of heaven, but to them it is not given.
12For whosoever hath, to him shall be given, and he shall have more abundance: but whosoever hath not, from him shall be taken away even that he hath.
13Therefore speak I to them in parables: because they seeing see not; and hearing they hear not, neither do they understand.
If only you had read the Bible, then you would know that the parables mentioned in the verses you quote were very clearly marked as parables. On the other hand the 6 day creation is not marked as a parable, the ten commandments are not marked as a parable, the hatred for the Nicolaitanes' actions is not marked as a parable.
2 Peter 1:20
Knowing this first, that no prophecy of the scripture is of any private interpretation.
If Jesus says He's talking in parables then He is talking in parables.
When God does not mention He's talking in parables, then it is not a parable.
It is as simple as that.