"Sin creates [an inclination] to sin; it engenders vice by repetition of the same acts. This results in perverse inclinations which cloud conscience and corrupt the concrete judgment of good and evil. Thus sin tends to reproduce itself and reinforce itself, but it cannot destroy the moral sense at its root."
Para. 1865, Catechism of the Catholic Church, 1994
Inscribed in ancient times at the Oracle at Delphi: "Know thyself." Self-knowledge follows closely behind the knowledge of God, and self-knowledge for anyone means knowledge of sin. "My own heart shows me the way of the ungodly." Scripture says we are all sinners, and we don't mind as long as the sins are nameless and faceless. When we name a sin found in ourselves (by Grace) it is as though we are confronted in the back alleys of our souls with furtive saboteurs and muggers who seek to prevent our union with God. The sudden self-revelation of a serious fault is one thing: the discovery of a deadly sin which we hate very much in others is worse. It is like finding out a spouse is unfaithful, or worse, that we have been blindly unfaithful to the Spouse of our soul.
The following pages on the deadly sins may lead to horrible discoveries. Bear in mind:
Friends will almost never volunteer this information.
If they do, we will not accept it.
God forgives anything, even repeatedly, so do not be afraid.
A combination of good spiritual reading (nothing too recent), nearly constant prayer, and reflection on the repetitive patterns of life works well for naming our sins. Remarks made in job performance reviews and conversations with people who dislike us are especially revealing. Our enemies usually lack the false charity to deny our sins. No wonder we are called to love them.
The human capacity for self-delusion is nearly limitless. We have all seen people claim great spirituality but do evil things and then ignore or rationalize them. Somehow we think we are immune to this phenomenon.