“For the hearts of these people are hardened, and their ears cannot hear, and they have closed their eyes— so their eyes cannot see, and their ears cannot hear, and their hearts cannot understand, and they cannot turn to me and let me heal them” (Matthew 13:15)

When Jesus was asked why He taught in parables, he answered with this quotation from Isaiah about the “hardened” hearts of the people. Jesus was aware of their unreceptive hearts, yet still poured out His. The Lord and His gospel still have that affect on people’s hearts. It either penetrates, making the heart new and receptive or it hardens it even more. When it is made new, it responds in sympathetic resonance to the sound of God’s heart. But when it is hard, sin dampens its heart strings, so that it is deaf to God’s love.