CCC 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 heart¹³³ Cf. Mk 3:5-6; Lk 16:19-31. do not diminish, but rather increase, the voluntary character of a sin.