Why is it a sin for a Catholic to leave the Catholic Church?

Attend a different church etc…

Because the Catholic Church is the one Jesus founded and it is the one true church.

Besides the Eastern Orthodox communities, where else is Jesus substantially present in the Holy Eucharist?

Even if they are baptised catholic but not sure what they believe?

What if they attend other Churches just to “check it out” or to (hopefully) meet a man?

Just for the sake of discussion (and please understand that I do not believe this myself) but this poses a circular argument.

“Why is it a sin to leave the Catholic Church?”

“Because the Catholic Church is the one true church.”

“Oh yeah, well who says so?”

“The Catholic Church.”

That’s almost like the joke that goes “You can’t post anything on the Internet that isn’t true.” “Where did you read that?” “On the Internet.”

I’ll bet there is not one single religious faith in the whole world - Christian and non-Christian alike - that doesn’t think it is the one true church.

Viewing this as an objective observer and not as a Catholic, what makes the Catholic Church “special”? Who, besides the Church itself, says this is true?

Leaving the One true church Jesus founded to meet a man from another religion puts meeting a man above Jesus. This is sinful in any christian religion.

You can read and study about other faiths, but you should be equipped with a strong background in Catholicism or it will further confuse you.

I would suggest reading the scriptures for you, unless you don’t believe in the bible .

Edited to add:especially–Acts

The only effective way to leave the church is to commit a mortal sin

this is because mortal sin cuts us off from the divine life of god

ie being in a state of mortal sin means you are not considered to be included among the members of the mystical body of Christ

however this state of being severed from the church might be remedied by repentance and seeking forgiveness of god. +

It’s really not that complicated.

Catholic church=full revelation of the truth

Walking away=walking away from what God has revealed

walking away from what God has revealed=walking away from God

Walking away from God=mortal sin=Hell (if you don’t repent)

Oriental Orthodox Church, Church of the East are some names.

I think it is a sin. But not for a regular cradle catholic. If you do infact know that the revealed truth is within the Catholic Church and choose to not remain in her, than it is a sin. But if you didn’t believe or know about this, than it wouldn’t be a sin.

Leave your denomination because of a spouse or esthetic reasons should never be the way you go about choosing your faith/denomination if you care about theology and/or truth.Reminds me about hearing about someone becoming a mormon, not because he believed its theology, but because he liked the Mormon culture and its services. Wether it was true didn’t make a difference. I can’t relate to that really. Truth should always be more important than the chance of finding a spouse or esthetic reasons.

I said (or at least implied) that my question was hypothetical and I don’t really need educated on the matter. But thank you for your response. :slight_smile:

If you attend another church just for curiosity, I don’t think it is a sin. (That should not replace Sunday mass at your catholic church).

Going to another church just to find a man is unwise. Mixed marriages are hard. Not wrong, but it will be extremely difficult and you should not be actively looking for someone with a different race. Falling in love with someone of a different religion is a different thing, but finding for someone in a place where you know is filled with non catholics is odd.

  1. This can be good to challenge your faith, figure out what you truly believe

  2. I know many Catholics (for various reasons) that attend protestant churches that still very much consider themselves to be Catholic.

  3. You could still end up back in the Catholic church after your trying other churches.

I have always believed in and encouraged people to explore other churches. There is no reason to blindly accept something just because your parents or your church tell you to. If you can on your own, through prayer and guidance, determine it is still the truth, then I would stay. But for some, they need to leave in order to find out that what they left was actually the truth all along.

On a more personal note:
I grew up Protestant and was taught that Catholicism is a flawed understanding of Christianity. Some went as far as to say it was a giant cult of pagans, thinking they were Christians. After abandoning my faith all together, and questioning things (mostly because I’m gay, which isn’t acceptable), I found myself over a couple years being drawn towards the Catholic Church (no idea why). I still believe the CC is the church established by Christ, even after praying and being prayed for for years to have my homosexuality taken away, I still very much consider myself to be Christian (though not Catholic because I am still in a sexually active same-sex relationship).

To willfully reject the Catholic Church knowing it to be the Church established by Christ is to cut oneself off from the grace of the sacraments entrusted to this Church, and without grace there is no salvation. There is no tabernacle in churches that deny the Real Presence and in communion you receive a mere piece of bread. It’s running away from a banquet to eat dry corn husks.

I don’t think this is accurate, actually. Committing mortal sin does separate yourself from the grace of God, but it does not cause you to leave the church. In fact, people living in mortal sin are encouraged to participate in all other areas of church life, outside of receiving communion.

The only way to “leave the church” in that sense is to be excommunicated, and that is something else entirely.

It is a sin to “leave the church” by way of going to another church and ignoring Catholicism because it is a sin to skip mass on Sundays for anything other than a grave reason. The Church did not found the Church, Christ did. He said so himself. Stick with Jesus and you can’t go wrong!

Actually my church doesn’t claim to be the one true church. We claim to be part of the one holy catholic and apostolic church, but we don’t claim out particular church is the one true church. And we’re not alone. Many Protestant Churches as well make no claim to being alone the one true church. Rather we claim to be part of Christ’s church.

To be fair, it’s not only Catholic Churches that contain tabernacles. And even the RCC agrees that select churches outside itself have the full grace of the sacraments, namely the Orthodox and Oriental churches. So this isn’t necessarily the best argument to present to the OP.

If the Church is not true than what is/is not a sin is not true. Therefore this entire thread would be moot.

If the Catholic Church is true then it would obviously be a sin.

Same applies to any religion if we are casting doubts…

In Islam it is a sin to leave, if Islam is true then it is a sin, if Islam isfalse then obviously it can not be a sin to leave…

To ask why something is a sin is to assume it has the backing of authority to be a sin :shrug:

Isn’t that claim in the same manner he says?

Like you claim to be X but only your claim backs it up until we meet God and have a steadfast answer?

So the idea that you are good to go in this sense has the same weight in the philosophical debate as the CC claim. Three options, you are right, the CC is right, all are wrong about religion.

But if you say the CC claim has no merit than the fact is your claim objectively has the same quantity of merit :shrug:

I am aware that it is considered a mortal sin neglecting to attend sunday mass without good reason

this is why I say you are considered outwith the life of god. +

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