Modern man experiences the threat of spiritual indifference and even of the death of conscience; and this death is something deeper than sin: it is the killing of the sense of sin. Today so many factors contribute to killing conscience in the men of our time, and this corresponds to that reality that Christ called “sin against the Holy Spirit." This sin begins when the word of the Cross no longer speaks to man as the last cry of love, which has the power of rending hearts. “Scindite corda vestra."
The Church does not cease to pray for the conversion of sinners, for the conversion of every man, of each of us, precisely because she respects, because she esteems, man's greatness and depth and rereads the mystery of his heart through the mystery of Christ.
April 1, 1979
(Pope John Paul II, “Love is the Explanation of Everything”, Rizzoli 2011, Page 14)