Scripture provides several lists of them. I warn you, as I warned you before, that those who do such things shall not inherit the Kingdom of God. These are what defile a man. But in the heart also resides charity, the source of the good and pure works, which sin wounds. It is corroborated by human experience.
Venial sin allows charity to subsist, even though it offends and wounds it.
But when the sinner's will is set upon something that of its nature involves a disorder, but is not opposed to the love of God and neighbor, such as thoughtless chatter or immoderate laughter and the like, such sins are venial. 1859 Mortal sin requires full knowledge and complete consent . It presupposes knowledge of the sinful character of the act, of its opposition to God's law. It also implies a consent sufficiently deliberate to be a personal choice. Feigned ignorance and hardness of heart 133 do not diminish, but rather increase, the voluntary character of a sin.