Isaiah Chapter 6, Speaking to Hardened Hearts. Vs 9-13

Isaiah 6:9-13 (KJV)
9 And he said, Go, and tell this people, Hear ye indeed, but understand not; and see ye indeed, but perceive not.
10 Make the heart of this people fat, and make their ears heavy, and shut their eyes; lest they see with their eyes, and hear with their ears, and understand with their heart, and convert, and be healed.
11 Then said I, Lord, how long? And he answered, Until the cities be wasted without inhabitant, and the houses without man, and the land be utterly desolate,
12 And the LORD have removed men far away, and there be a great forsaking in the midst of the land.
13 But yet in it shall be a tenth, and it shall return, and shall be eaten: as a teil tree, and as an oak, whose substance is in them, when they cast their leaves: so the holy seed shall be the substance thereof.