Sins can be distinguished according to the virtues they oppose , by excess or defect, or by commandments they violate . Sins can be classed according to the person they concern , whether they concern God, neighbour or oneself. Sins can be divided into spiritual and carnal sins. Sins can be divided as sins in thought, word, deed or omission . Actual sins are the sins we actually commit.
Sins do differ in their seriousness and are rightly evaluated according to their gravity.
The Church, supported by Scripture and human experience, makes the distinction between mortal and venial sin. Grave matter is specified by the gravity of the offence against the Commandments and by the person offended. Mortal sin is always a radical possibility because of our human freedom. Mortal sin kills the life of God's grace in our soul. It turns us away from God, who is our ultimate happiness.