Mortal Sin or not?

So, this morning my little sister had to do something called a “moon journal” for school thtat your supposed to do every night. She honestly forgot to do it this weekend, so I helped her. She did the dates she missed this morning, and I helped her. Unfortunately, she had to write it on the night it occured, so she had to do them today. We used the internet, and I just wrote the low temperature for the night and a random time. If she doen’t tell her teacher she did it this morning, am I helping her commit a mortal sin by lying?

You are starting to post here with numerous every day occurrences thinking they are mortal sins, or worried they are mortal sins.

STOP! You need to make an appointment with your pastor and tell him of your scrupulous thoughts. You need consistent spiritual direction from one person to help you see that these worries and intrusive thoughts are not normal.

You cannot come here and ask if everything you do is a sin.

Are you are saying that you decided to help her to fake her homework and then did that? If so, that act is already completed and does not depend upon her not revealing it, and in addition it is bad example (scandal). Being mortal also depends upon knowledge and prior reflection which a priest can help you with if you cannot determine it.

What he said. ^^^^

Somewhat. I told her to tell her teacher the truth: My dad was sick this weekend, so she didn’t get to do them. I told her to simply tell her teacher she did it this morning. I feel like it’s such a trivial thing, that at worst wouldn’t it be venial?

I told her to do the right thing and tell her teacher she did it this morning.

You told your sister to inform her teacher that she did her homework this morning, so why are you worried about *mortal *sin? Even if you had helped her fake her homework and didn’t tell her to inform her teacher about it, I don’t think it would be considered a mortal sin because I don’t think the matter is considered grave. But it would still be wrong and sinful for you to help her fake her homework (bad example, scandal). God bless you.

EDIT: If the consequences of what you did were grave (e.g. you gravely endangered your sister’s soul), then I’d worry about mortal sin being involved. Did you subject your sister’s soul to such grave consequences? I don’t know if you did and you don’t have to answer that you did in a post. If you think that you did, then confess to a traditional priest. God bless you.

Obviously it is wrong to help her fake the homework, but if it was the sin of scandal is it mortal, or venial because it lacks grave matter?

Lying, in this case, is likely venial, no?. I don’t necessarily think that gravey endangers her soul, expecially if she’s telling her teacher the truth.

You worry too much.

I know I worry too much, but I’m stil looking for an answer lol

I’m afraid I’m just trying to be perfectly safe – I don’t know the girl’s soul and can’t assume anything about her, neither can I guess how her brother’s behavior effected her. If she were an inveterate liar and cheater, maybe her brother helping her fake her homework could seriously hurt her by confirming her in her sins of lying and cheating. God bless you.

When you say “wrong and sinful”, are you meaning it to be venially sinful do to the lack of grave matter?

I think there is not grave matter here, but only you could know this, no? If your sister is a big and major liar/cheater and she couldn’t be trusted to pass on info to her teacher, then you may have hurt her soul in a serious way by giving her your assent and by confirming her in her sinful lying/cheating. But my guess is that your sister is not a big and major liar/cheater and can be trusted;, and thus, would not be gravely harmed by the way you “assisted” her. I think what you did was only venially sinful due to lack of grave matter, if there is indeed no grave matter. Know that I am not a priest and am far from an expert on these matters. Just speak with a traditional priest, he’ll ease your mind. God bless you.


One thing you are overlooking is the authority of the teacher to tell her students WHEN they must do a certain assignment, which I do not think the teacher has. If there is a reason, such as the time when certain celestial bodies are visible, that might be a valid reason, but It appears to me that the teacher wants this every night of the semester. I do not believe the teacher has the right to exert that much control over his/her students’ lives.

Teachers can assign work that must be done outside of class; when it is done is beyond their authority.

In my eyes, your sister did not commit any sin, nor did you.

No it’s not

If it is insignificant, then lying about the assignment would not be greatly desirable. It is good that you told her that, because to gain advantage through misrepresentation demonstrates a lack of charity towards other students, and disrespect of the teacher through a betrayal of trust.

I would recommend you have a “regular confessor” who can assist in your on going formation of conscience.

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