In the account of the Passover in the book of Exodus (Shemot) we learn that Yah desires to close off Pharaoh's heart, so that he becomes incapable of compassion and empathy for the Israelite people. This, of course does not relate to a physical heart, but a spiritual one. When I thought about this, I couldn't help but wonder how miserable an existence this would be. To have no hope of changing, growing or repenting is an incomprehensible condition. Pharaoh's heart-hardening process eventually lead to his own death, as well as the death of his firstborn son.
Rabbi Shlomo Ben Levy explains how and why Yah hardens hearts. Sometimes people harden their own hearts. We must be aware of this and be willing to perform acts of loving-kindness. The Rabbi refers to this as doing "spiritual CPR."
Here's an excerpt from the article: "What cure is there for a hard heart? Well, assuming that [Yah] has not made it your fate, there is much that we can do. I say we because the harsh realities of life are such that we all find ourselves being harder than we want at times. [The Most High] told Ezekiel that 'I will put a new spirit within you, and I will take the stony heart out of their flesh and will give them a heart of flesh.' (Ezekiel 11:19). We must want this."
For a free download of The Heart: A Passover Midrash by Shlomo Ben Levy, visit: http://www.blackjews.org/articles.htm see: Hardening of the Heart: A Passover Sermon.