Am I guilty of mortal sin even though I was ignorant?

Dear Apologist,

I was brought up in an atheist home and didn’t have very many moral values. I ended up committing grave sins against God’s commandments. However, I didn’t know that they were sins at the time since I didn’t even believe in God. In the Catechism of the Catholic Church (1860) it is written that no one is deemed ignorant of the moral law written in our conscience. Does this mean that I sinned mortally even if I didn’t think what I did was wrong (for that matter I didn’t think such a thing as a “wrong” existed :frowning: ).


The principles of moral law that no one is deemed to be ignorant of are generally those contained in the Ten Commandments. Across cultures those of all religions and of none have recognized the immorality of killing, stealing, lying, and adultery; they have also recognized the importance of honoring parents and setting aside adequate time for rest from ordinary responsibilities. Because these principles seem to be embedded in the moral conscience of man (cf. Rom. 2:15-16), this is why no one is deemed ignorant of the principles of moral law. Indeed, many of the prohibitions of the Ten Commandments are written into civil laws and so those who do not know the moral illegitimacy due to religion would know it due to the civil code.

However, as Paul acknowledges in Romans 2:16 only God can judge hearts and know the culpability for sin of an individual soul. If you broke the civil code, ignorance would not be an excuse because humans cannot read your heart and know your personal level of culpability; but ignorance of the moral law is known to God and he will judge accordingly.

If you were baptized when you entered the Church, all of the sins of your past life and all temporal punishment due them have been wiped away, so you need not worry about them. If you were already baptized and made a sacramental confession of the sins you committed since baptism when you entered the Church, those sins have been forgiven. Try not to let past sins haunt you because those thoughts are really temptations to despair of God’s mercy, love, and forgiveness. God bless.

**Recommended reading:

Understanding Scrupulosity** by Fr. Thomas Santa, C.Ss.R.

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