In passage we know well, where Jesus explains that the people look but do not see, hear but do not listen or understand, in St. Matthew's version there is a diagnosis given. He says that
The hearts of the people "epachenthe" (a verb that means to become thick or enlarged). Mt 13:15.
In modern medicine we call it cardiomyopathy. The heart muscle becomes thick, enlarged and/or rigid. The real danger of cardiomyopathy is that often there are no signs or symptoms. The people who have it don't even realize it. It develops slowly in most cases. And over time it kills.
The cardiomyopathy Jesus is talking about is of course spiritual not physical. It also usually happens gradually over time. So much so that we don't even notice. Our hearts become thick, and rigid. Our concern for others slowly disappears, beginning with people we don't like, then people we don't know, an ever shrinking circle of concern, until the only one we are focused on is ourselves. As the disease progresses, "thy will be done" becomes "I like things done a certain way." We only listen to people who think like us.
This spiritual cardiomyopathy is far more deadly than the physical form. It can rob us of eternal life.
The good news is that it is completely reversible. The treatment begins with a thorough examination of conscience. For the Catholics, this should be followed by a trip to the confessional. And then, the only way to keep it from reoccurring is daily prayer. And not just that prayer where we pray for ourselves and or friends and family, but real Christian prayer where we exercise the muscle of our heart and we pray for people we don't like, people whose actions we don't understand.
Part of the reason we need to go to mass and not just pray by ourselves is that we need to get together with the grumpy old man, the negative woman, the crying baby. We need to pray surrounded by people who are imperfect, just like us. We need to sit shoulder to should with the mess of humanity and remember that God loves us all equally, and we equally need God's grace.
Take a moment today do a self-examine. Truth be told, we all suffer, particularly as we get older, from a little heart disease. But the spiritual kind only kills us if we let it. The cure is always available. Our hearts can always be restored to perfect health, with the grace of God.