Do we always obliged to rebuke people whenever we see them going the wrong way?
Take example of me & my brother. There were times where I think I know he’s going to get into trouble, or he’s going to get us into trouble. But I let him do whatever he wants… Well, in the end he did get into trouble, or he did get me into trouble, where my mother mad at us like crazy. And I can only cry because of it
Since he is your brother and, I hope, you have a decent relationship, you should tell him when he’s going wrong. Don’t get preachy since that’ll turn him off. Just say it straight: “(brother), you’re going to get into trouble if you do that.” But, don’t expect him to listen. He might not. But you’ve tried to warn him at least.
I noticed you said, “he did get me into trouble”. I’m sure it does feel like that, but that’s really not the truth. He might have the idea. He might be the leader. He might be doing whatever he can to convince you to go along. But, you get yourself in trouble when you go along with him. You have your own conscience and you seem to have a good understanding of right and wrong. You need to be strong!
Try to stop things at the idea stage so that you don’t get in too far. If he won’t quit, then tell him you’re leaving, that it is wrong, and you don’t want trouble. Then leave. It will be hard, maybe, but you will be acting as a great example for your brother and you may save him from sin. Don’t you think that’s worth it?
As for other people who are not as close as a brother is, it is a bit more difficult to let them know. Sometimes they don’t trust you or love you. I think you need to be sure it’s someone who you have a relationship with, or it needs to be a really important thing, like standing up to a bully.
Mostly as a young person, your main focus needs to be learning all you can about the faith and what it means in your life.
My parents did not care for a chronic tattle tale. However, we knew very well that we better not go along with some “stupid” idea our sibling had if we knew it was wrong. We were taught to let the other know if something would get them in trouble, and to let our parents know if they continued in a bad direction.
Consequently there were few times any of us had to report the other. As we got older the responsibility of our behavior was our own. As far as anything that might get us in deep trouble with the law my dad simply warned us that we better plan on spending the night in jail. He told us there would be no rescue on his part, and if we were guilty of a crime we better confess.
Our father also expected the truth. He told us he might be disappointed in something we did, but he much preferred to hear it from us first. We learned early on that no matter what kind of mistake we might make, or trouble we might get into, the truth was better than trying to hide or lie about it. Sure he was mad or disappointed, but if we had lied then he was outright peee—ooooood.
Warn your brother, be responsible for your own actions, and tell him he is responsible for his.
There isn’t any problem with allowing someone to suffer the natural consequences of their actions. (Of course, this assumes nothing will be damaged or destroyed and no person will be harmed. But you seem bright enough to know that!) Just be sure you aren’t “helping the consequences along”. They need to be natural. No tattling to make sure he gets in trouble or things like that. And if brother asks you what he should do, tell the truth. You need to be able to trust each other!