In the Bible, specifically at 1 Timothy 5:24, we are told that some men’s sins are obvious before they go to judgement and precede them there, whilst the sins of other men follow them to judgement. In other words, some sins are worse than others and quite obvious, whilst others are less obvious and of a lesser consequence, so we have two classes of sins just from the Bible!
The Church has “classes of sins”. There is Original sin, Mortal sins and Venial sins and there are also spiritual sins and carnal sins.
The Catholic Catechism states at 1853 -
Sins can be distinguished according to their objects, as can every human act; or according to the virtues they oppose, by excess or defect; or according to the commandments they violate. They can also be classed according to whether they concern God, neighbor, or oneself; they can be divided into spiritual and carnal sins, or again as sins in thought, word, deed, or omission. The root of sin is in the heart of man, in his free will, according to the teaching of the Lord: “For out of the heart come evil thoughts, murder, adultery, fornication, theft, false witness, slander. These are what defile a man.” But in the heart also resides charity, the source of the good and pure works, which sin wounds.
I found this list of possible mortal sins and it could be argued that each one would constitute a ‘class’ of sin -
Anger,
Adulterers,
Amending the words of the Holy Bible,
Blasphemy against the Holy Spirit, (Eternal sin)
Carousing,
Cowards,
Defrauders,
Dissensions,
Disrespect towards parents,
Drunkenness,
Enmities,
Envy,
Factions,
Faithless,
False witness (liars)
Fornicators,
Greed,
Holy Communion received while in a state of mortal sin,
Idolatry,
Impurity,
Jealousy,
Licentiousness,
Love and practice falsehoods,
Male prostitution,
Murderers,
Polluted,
Quarrelling,
Sodomites,
Sorcery,
Strife,
Thieves (steal/robbers).
I suppose if you committ a certain ‘class of sin’, then you become a certain ‘class of sinner’!!