Do we need to confess past sins that we didn't know were sins at the time?


I am a lifelong Catholic, in my 40’s, who has always had strong faith, attended mass weekly (with a few exceptions), and have always prayed daily, observed Lent, etc. Here’s the thing - I did not go to Catholic school growing up, and my “Catholic education” ended after my confirmation as a young teenager. Meaning, I never was taught “theology of the body”, or even what things were considered moral and grave sins sexually. My parents, born and raised in Central America, never talked to us about sex, birth control, or anything in that regard. We were just assumed not to have sex until we were older, as we were raised in a very strict (not allowed to date until after high school), but loving environment. I think my parent’s M.O. was to keep my sister and I on a tight rope, so they wouldn’t really need to talk to us about sex.

Going to public schools, then off to college, with mostly all secular friends (and reading silly magazines like Cosmopolitan and others), I was surrounded by stories of sex, and how “waiting for marriage” was just an old-fashioned idea, and that “masturbation is completely normal”, etc. All this said, my “sexual moral education” came from the mass media / secular society. Somehow in my immature brain of my 20’s, I never connected the dots to think that sex before marriage, or contraception, was sinful.

It wasn’t until recently when I became very interested in learning more about Catholicism, participating in bible studies, reading Theology of the Body and the Catechism of the Catholic Church, did I realize how off track I was in my 20’s. Since I had engaged in pre-marital sex and took oral contraception before getting married, I was sinning gravely (without realizing it) and receiving the Eucharist each week at Mass. Do I need to confess these past sins (that I didn’t know were actually sins at the time) in my next confession? And, is my past sexual behavior considered “grave sins” since at the time I was completely ignorant about it? How I wish I had been taught Theology of the Body when I was growing up, and given a copy of the Catechism at my confirmation! What a difference it would have made! I’m trying not to beat myself up about it, but I do want to know if - with this revelation - if I need to go to confession about them. Thank you for your answers and feedback.


I would play it safe and confess every single sin you can think of that you committed. There’s no reason not to. There’s grace in confessing venial sins.


I would think yes. You are now aware that it was a sin and should pray and ask for forgiveness and to not do it again. Have you learned the rosary?


Honestly, it always feels good to confess sins. However, I would ask my priest about this one to know for sure. I used the Ten Commandments examination of conscience and went back 30 years - that was quite the confession. I have heard to always end confession with ‘and any sins I may have forgotten’ Hint: you can’t ‘forget’ on purpose. Hope this helps a little.


Yes, I’ve been praying the rosary since I was a kid :slight_smile:


When I’ve had hidden sins revealed to me, I’ve always confessed them prior to receiving holy Eucharist again. He makes all things new👍


If you did not know it was wrong when you did it. It is not a sin. Period!


I think of confessing past sins as a way of breaking all ties with Satan. Every sin is an instance where I have agreed with Satan, knowingly or unknowingly.


There are these three things that you need to have done to have committed a mortal sin. These are that the sin is concerned grave matter, done with full knowledge and full consent. If one of the three is missing, then it’s not a mortal sin. BUT I do really want to encourage you to confess the sins anyway, because it’s a great way to get a stronger and better relationship with God. Also I would say that it’s great to distant yourself from the sins. Personally, confession is the only thing that makes me stop beating myself up when I have committed a sin that I fully regret, so I recommend you strongly to go to confession.


If you were ignorant, you are not culpable for the sins. Venial sins may be confessed, they are also omitted at Mass, by reception of Communion, etc.


It’s still serious sins but you are not morally responsible in such a way that you are if you knew that it was a sin. But for your own sake it’s good to be fully reconziled with God in a way that you know you have nothing unsaid, and since you obviously regret the sins, then I would recommend going to confession.


Thanks for the feedback, all! I will plan to head to confession this Saturday - I like the idea of distancing myself from those sins, and starting anew - especially as I prepare to raise two teenagers. Thankful for Theology of the Body to guide me with that!

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