Matthew 13

13 That’s why I speak to them in illustrations. For even though they see, they don’t see; and even though they hear, they don’t hear; nor do they understand.*13:13. Jesus was referencing the Old Testament here. It could be any of these: Deuteronomy 29:4, Isaiah 42:20, Jeremiah 5:21, Ezekiel 12:2.

14 The prophecy of Isaiah is fulfilled in them: ‘Even though you hear, you won’t understand, and even though you see, you won’t perceive. 15 They have a hard-hearted attitude, they don’t want to listen, and they’ve closed their eyes. If they didn’t they might be able to see with their eyes, hear with their ears, and understand in their minds. Then they could return to me and I would heal them.’*13:15. Quoting Isaiah 6:9-10.