The truth is not all fights are worth engaging in. We should take some "nonsense" sometimes. Not every one that offends us needs to be given a dedicated/fighting attention. We need to learn to choose our fights. And I don't mean the roll-on-the-floor with punches kind of fight. If you are not a boxer or wrestler I don't think you should ever be involved in an exchange of punches. So I would say the first rule in choosing your fights is to never choose a punch-me-I-punch-you fight.
So what kind of fight am I talking about? I'm talking about white-collar fights like civil disobedience, giving someone a piece of your mind, the silence treatment, throwing a spanner into the wheel of the person you are annoyed with, showing him you are the boss, and going all nuclear without melting or throwing a punch. These are usually fights we are proud of fighting, we love making heroic stories out of them. Nevertheless, we shouldn't be involved in all the fights we have a reason to be in. We should learn to pick our fights.
For instance, I don't get involved in vocal fights. You'll never find me shouting at anyone. It gives me headache and I will keep thinking about everything I said for the entire week. Those kind of fights are not worth the trouble for me. But there's another kind of fight I love getting into. I once worked in a company where the internet was blocked. You can't access your email or do a small google search. One day I stayed back after work and started trying all the IP addresses in the network range. I couldn't finish that day so I continued the next day and the day after that. Then I discovered 2 IP addresses that could access the internet. I gave one to my colleague and I took the other. Any day I come to work and I see someone using my IP address I begin a war. I remotely force him/her to use another IP and I take my IP back. I don't take that kind of nonsense. (Even though it sounds irrational to call a particular IP mine just because I discovered that it had internet access. But all fights are like that, they've got high irrationality content).
I'm very selective in the fight I get into. I don't do civil disobedience. I don't fancy fighting a government that doesn't know or care about my existence. Not everyone should be like me in this regard; it's just that's the way I am. Just like I don't engage in vocal fights. You'll seldom find me participating in a protest. I'm a natural silence treatment professional. Without intending to or noticing, I shut out people who are giving me troubles. You can fume all you want and threaten all you can, I'll keep quiet and do just the very thing you don't want me to do. It's a type of fight that I'm powerless against, it chooses me. I also don't wish people ill-luck or throw spanner into their wheel of progress. I'm the kind of guy how will save a drowning murderer, and not because I want him to reform but just because I can't stand seeing him drown. If I can help you, I will (sometimes) even if you don't want me to. So you'll never find me saying to someone else that "I will show you!"
Fighting is all about picking a fight you can bear losing. As a christian, that reduces the number of fights you can engage in. You shouldn't think you can bear the loss of your own soul. Then among the remaining types of fight you can engage in, a few won't be worth the trouble. So in the end, it's about understanding yourself and your beliefs, then picking a fight that won't contradict them.