Q: What are sins against the Holy Spirit? -A.C.
Answered by Fr. Edward McIlmail, LC
A: The offense against the Holy Spirit that stands out is the one Our Lord calls an unforgivable sin. The Catechism in No. 1864 says, “‘Therefore I tell you, every sin and blasphemy will be forgiven men, but the blasphemy against the Spirit will not be forgiven” [Matthew 12:31; cf. Mark 3:29; Luke 12:10]. There are no limits to the mercy of God, but anyone who deliberately refuses to accept his mercy by repenting, rejects the forgiveness of his sins and the salvation offered by the Holy Spirit. Such hardness of heart can lead to final impenitence and eternal loss.”
Pope John Paul II explains that that unforgivable blasphemy consists “in the refusal to accept the salvation which God offers to man through the Holy Spirit” (Dominum et Vivificantem, No. 46). It is a sin of stubbornness that rejects God’s mercy.
Other sins against the Holy Spirit are commonly said to be: despair, presumption, obstinacy, resisting truth, and envy of another’s spiritual welfare.
“By despair,” explains the Catechism, No. 2091, “man ceases to hope for his personal salvation from God, for help in attaining it or for the forgiveness of his sins. Despair is contrary to God’s goodness, to his justice — for the Lord is faithful to his promises — and to his mercy.”
No. 2092 of the Catechism explains, “There are two kinds of presumption. Either man presumes upon his own capacities, (hoping to be able to save himself without help from on high), or he presumes upon God’s almighty power or his mercy (hoping to obtain his forgiveness without conversion and glory without merit).”
Obstinacy is resisting the Holy Spirit, being stubborn and persisting in sin.
Resisting the truth can take various forms: attacking it by word or argument; contradicting it; challenging it as false.
Envy of another’s spiritual welfare in effect involves questioning God’s judgment about the gifts he distributes.
For further reading, see The Catholic Encyclopedia article. I hope this helps. God bless!