Parables: When Ordinary Warnings Are No Longer Heeded

Then the disciples came and said to [Jesus], "Why do you speak to them in parables?"...

This is why I speak to them in parables, because seeing they do not see, and hearing they do not hear, nor do they understand. Indeed, in their case the prophecy of Isaiah is fulfilled that says:

'You will indeed hear but never understand, and you will indeed see but never perceive. For this people's heart has grown dull, and with their ears they can barely hear, and their eyes they have closed, lest they should see with their eyes and hear with their ears and understand with their heart and turn, and I would heal them.' [Isaiah 6:9-10]

But blessed are your eyes, for they see, and your ears, for they hear.
Matthew 13:10, 13-16

Symbolic parables cause those who "have ears to hear and hear not" to misunderstand further. The literary form of symbolic parable (mašal) "appears whenever ordinary warnings are no longer heeded (cf. Matt. 13:10)," and no warning will ever be heeded by hardened people who are intent on continuing in disobedience. This is the point of Isa. 6:9–10, where the prophet is commissioned to tell Israel to "keep on listening but do not perceive.… Render the hearts of this people insensitive, their ears dull … lest they … hear with their ears … and repent and be healed."

--Beale, G. K. (1999). The book of Revelation : A commentary on the Greek text (237). Grand Rapids, Mich.; Carlisle, Cumbria: W.B. Eerdmans; Paternoster Press.

He who has an ear, let him hear what the Spirit says to the churches.
Revelation 2:7