Sin, mercy and conversion
Sin is a failure of love toward God and neighbor that wounds the person and communion. Catholic teaching distinguishes mortal and venial sin; mortal sin requires grave matter, full knowledge, and deliberate consent. Not every grave-looking situation reveals another person’s responsibility. Mercy calls for truthful acknowledgment, repentance, and conversion, while scrupulosity requires patient, wise accompaniment rather than endless self-accusation.
Follow the sources
An original library introduction, with sources for further study. This is a starting point rather than a complete treatment or a finished formation lesson.