Am I Sinning?

[Eternal CB]

im about to graduate from my final year in high school. our school is having a Mass, but there are a lot of students in my year who are not devout, and i'm almost sure they have committed mortal sin which has been unconfessed. i know this because they brag/talk about it to me and to others, for example getting drunk, having unmarried sex etc. my question is, is it a sin of omission if i dont warn them to not take the Body/Blood of Christ because they are in a state mortal sin? thank you and God Bless!

P.S. i've attempted spreading God's Word to a handful before, but they have rejected it.

[Pontifex]

No, you are not sinning by being silent in this situation. First and foremost, since this is a Catholic school it is the responsibility of the school chaplain, priest, who has been sent there to minister to inform the consciences of your fellow students about morality and proper reception of the Eucharist. My advice to you, is to lead by example as I'm sure you already do. Express your love for the sacraments and especially your love for the Eucharist and the powerful impact that confession makes on you. When you make it personal and from your experience people are more likely to listen and think about their own lives in comparison, even if they do not seem receptive to it.