How serious a sin is plagiarism?

I daresay it’s reasonable to suppose that most Christians probably believe in a hierarchy of sins and I was wondering if those that do consider plagiarism to be amongst the more serious sins?

Feel free to offer your (own) opinion and state your (own) reasons.


In my opinion, plagiarism is a serious sin. The reason I say serious is because:

  • It is theft of another persons work

  • There is a deliberate action to deny credit where credit is due

  • It is deceitful and dishonest

  • It could harm the author of the plagiarized work

  • It shows a total lack of integrity

They are just a few that spring to mind.

So, in short, in the hierarchy of sins, it’s a serious one !!

Comment duly noted. Although the actions of OneTrueCathApos prompted my Original Post I wonder if I might gently request that any discussion on this thread focuses upon the sin itself?


Edited to comply with your respectful request :thumbsup:


Thank you for being so accommodating. I’m interested in the Catholic viewpoint on this question because there is an exclusively Catholic doctrine that some sins are venial and other sins are mortal. I should have thought that for a Catholic it’s got to be a mortal sin (assuming the Catholic has full knowledge) but I couldn’t find anything in the Cathechism of the Catholic Church to endorse my notion.


I think this makes it perfectly clear:

2454 **Every manner **of taking and using another’s property unjustly is contrary to the seventh commandment. The injustice committed requires reparation. Commutative justice requires the restitution of stolen goods.

Oh yes - it’s theft plain and simple - and I would therefor guess a mortal sin, not a venial sin.

In my opinion of course :wink:

Shouldn’t this be in the moral theology forum? :confused:

I also think

2451 The seventh commandment enjoins the practice of justice and charity in the administration of earthly goods and the fruits of men’s labor.


2453 The seventh commandment forbids theft. Theft is the usurpation of another’s goods against the reasonable will of the owner.

make it perfectly clear that plagiarizm is a serious sin. There is no justice and charity in copying the work of another person’s labors and passing them off as your own.

From the catechism of the catholic church

Taking copyrighted material and posting them on a nother forum as though they were your own is clear usurpation of another’s goods.

Thanks. Yes, it’s certainly theft but I think for a Catholic the seriousness is determined by the value of whatever is stolen. I’m thinking along the line that there is more to this sin than just theft.


Possibly. I chose this forum because I’m also interested in the non–Catholic view and this forum is where the non–Catholics are allowed to hang out.


I think it is primarily theft. Whether mortal or venial would depend on the value taken. I suppose if one passes it off as ones own and claims fame and credit thereby there is a sin of lying again mortal or venial depending on how serious the deception is. It would probably be a minor deception if one was just impressing ones friends, but major if one was deceiving a potential employer.

Note that this is just my :twocents:. I haven’t given it deep thought or serious research.

I think this whole thread is rather ridiculous. It is obviously focused at me which is absurd. Guyonthestreet made a mountain out of a molehill because he is here on these forums to put people down, to try and make fools of them, to show he is the one who knows it all, when in fact he is sinning from the very things he does here.
For a “Christian” he certainly doesn’t act like one. Let’s see him cast the first stone.
Some sins are more drastic than others. In the end, the difference might be moot.
To forgive is divine.

Calvinists which he sounds like one, do not believe that all sins can be washed away. Protestants also reject the Catholic distinction between mortal (very serious) and venial (less serious).
Early church fathers thought that only murder and adultery deserved the name of sin.
Exodus 34:6-7:
Man’s capacity to sin can never exceed God’s capacity to forgive.

I doubt if anyone here, ANYONE has never not once, either copied one line or a paragraph from someone else. If anyone here copies anything from the bible, then we are ALL guilty of it.

Most of the time when people quote the Bible, they do cite the source (ie book, chapter, and verse).


Can anyone cast the first stone?**

Since we’re discussing severity of sins (i.e., mortal and venial) this is not something that Catholics ‘made up’. Scripture itself says, 1 John 5:16:
16If any man see his brother sin a sin which is not unto death, he shall ask, and he shall give him life for them that sin not unto death. There is a sin unto death: I do not say that he shall pray for it.

A sin unto death is mortal sin (mortal-deadly). Obviously, St. John distinguishes that there are sins which are not unto death (venial, or not deadly) as well as this mortal sin.

So this is not an ‘exclusively Catholic’ doctrine, is it? It is a Christian doctrine (which all Catholic doctrine is but that’s for another thread) but apparently it’s a Christian doctrine which is not accepted by some nonCatholic Christians?

I’m certainly not suggesting that this is something that Catholics “made up” but as the Catholic interpretation of 1 John 5:16 is not shared by any other faith community inside Christendom the inescapable conclusion is that this is indeed an exclusively Catholic doctrine whereby the Catholic Church using exclusively Catholic nomenclature categorizes sins according to exclusively Catholic criteria.

So, within the Catholic parameters of understanding, do you think plagiarism is a mortal sin or a venial sin?


I don’t know if Catholics would consider it a mortal or venial sin but the bible talks about different levels of punishment and it seems that harsher punishment may be due when a person is made aware of a sin and still does it.

Luke 12:47-48, “And that servant, which knew his lord’s will, and prepared not himself, neither did according to his will, shall be beaten with many stripes. 48 But he that knew not, and did commit things worthy of stripes, shall be beaten with few stripes. For unto whomsoever much is given, of him shall be much required: and to whom men have committed much, of him they will ask the more.”

Based on this passage, it seems that the greater our knowledge, the greater our responsibility to do what is right…also…the greater our punishment if we don’t.

Plagarism is not necessarily stealing.

It depends on the context of the act if it is sinful at all. If ones claims to be the author of something written by another person it could be lying. Lying is generally not a mortal sin, but can be. Lying with the wilfull and malicious intent to do harm to someone would be grievous evil, called calumny. Lying to your wife when she asks you if her outfit makes her look fat is not so evil.

Using another person’s work, but varying it to come up with one’s own version is not plagarism. Someone might take a recipe and make changes to it for example.

The polite practice of citing one’s sources, referencing the person whose work or ideas you repeat to incorporate into your own is relatively modern, even in scientific literature.

Trying to deliberately harm another person’s reputation, by accusing that person of some sin for example, even if the accusation is true, has always be seen as a grievous evil. It is called the sin of detraction. It is motivated by malice. This would always be a mortal sin if the conditions for committing a mortal sin were present.

I would have to disagree, Grandfather. By definition, plagiarism is stealing. In fact, it comes from the Latin plagiarius (abduct) and plagiare (steal). Another translation could be “kidnap.”

That seems like politician-speak and skirting to me. Using someone’s intellectual property and passing it off as one’s own, or even giving the appearance that it is one’s own, seems like a willful lie, or at best a sin of omission.

In the case of copyright infringement (as the case that has been in question on this forum was), it goes beyond plagiarism; it’s unlawful behavior. Plagiarism is dishonest ethical behavior; copyright infringement is against the law. Plagiarism is enforced by a community standard; copyright infringement is enforced by the courts (see “Plagiarism and Copyright - What Are the Differences?” - The Council Chronicle, Nov. 2005, as cited by Plagiarism In short, if Dave Armstrong wanted to, he could inform the court that OTCA violated copyright infringement by posting his words on the CAF Forum and passing them off as hers (OTCA’s).

The Writing Program Administration Council, which is the gold standard of academia, defines plagiarism this way: plagiarism occurs when a writer deliberately uses someone else’s language, ideas, or other original (not common-knowledge) material without acknowledging its source. The following has even been suggested in the academic world, and surely we would want to follow it here in a Christian context:

We’re here to better ourselves and to better our communities. You can’t do that by stealing. To avoid plagiarism:

  1. Do not use someone’s words without referencing the source or including the information in quotation marks or a block quote; and
  1. Do not use someone’s ideas without referencing the source.

I think those are good guidelines.

I beg to differ; times have changed (especially with the Internet and cut-and-paste), and I think it goes beyond polite. It is an accepted and mandated ethical standard in science and in industry. I agree with you Grandfather; it is all about context: in Christian apologetics, do we really want to practice deception? Surely we want to be at least as ethical in the Christian community as the scientific and industrial communities are, don’t we?

Pax vobiscum,


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