Romans 9:18 So then he has mercy on whomever he wills, and he hardens whomever he wills.
Exodus 4:21 And the Lord said to Moses, “When you go back to Egypt, see that you do before Pharaoh all the miracles that I have put in your power. But I will harden his heart, so that he will not let the people go.
John 12: 36
The Unbelief of the People
When Jesus had said these things, he departed and hid himself from them. 37 Though he had done so many signs before them,
they still did not believe in him, 38 so that the word spoken by the prophet Isaiah might be fulfilled:
“Lord, who has believed what he heard from us,
and to whom has the arm of the Lord been revealed?”
39 Therefore they could not believe. For again Isaiah said,
40 “He has blinded their eyes
and hardened their heart,
lest they see with their eyes,
and understand with their heart, and turn,
and I would heal them.”
Isaiah 6:6 Then one of the seraphim flew to me, having in his hand a burning coal that he had taken with tongs from the altar. 7 And he touched my mouth and said: “Behold, this has touched your lips; your guilt is taken away, and your sin atoned for.”
Isaiah's Commission from the Lord
8 And I heard the voice of the Lord saying, “Whom shall I send, and who will go for us?” Then I said, “Here I am! Send me.” 9
And he said, “Go, and say to this people:
“‘Keep on hearing,[c] but do not understand;
keep on seeing,[d] but do not perceive.’
10 Make the heart of this people dull,[e]
and their ears heavy,
and blind their eyes;
lest they see with their eyes,
and hear with their ears,
and understand with their hearts,
and turn and be healed.”
11 Then I said, “How long, O Lord?”
And he said:
“Until cities lie waste
without inhabitant,
and houses without people,
and the land is a desolate waste,
12 and the Lord removes people far away,
and the forsaken places are many in the midst of the land.
13 And though a tenth remain in it,
it will be burned[f] again,
like a terebinth or an oak,
whose stump remains
when it is felled.”
The holy seed[g] is its stump.