When we understand God’s word and turn, He would heal us

Mt 13:15

                ¹⁵ For this people’s heart have become calloused; they hardly hear with their ears,
   and they have closed their eyes. Otherwise they might see with their eyes, hear with their ears,
   understand with their hearts and turn, and I would heal them

Isa 6:10

                ¹⁰ Make the heart of this people calloused; make their ears dull and close their eyes. Otherwise they might see with their eyes, hear with their ears, understand with their hearts, and turn and be healed.”

John 12:40

                ⁴⁰ “He has blinded their eyes and hardened their hearts, so they can neither see with their eyes, nor understand with their hearts, nor turn—and I would heal them

Acts 28:26, 27

                ²⁷ For this people’s heart have become calloused; they hardly hear with their ears,
   and they have closed their eyes. Otherwise they might see with their eyes, hear with their ears,
   understand with their hearts and turn, and I would heal them