Matthew 18:1 and following records an occasion when Jesus' disciples asked, "Who is greatest in the kingdom of heaven?" Previous to this occasion, three of the disciples had accompanied Jesus to the top of a mountain and been witnesses to His transfiguration. Possibly this event had prompted the question. But this was not the only occasion on which the question was raised by the disciples.
We know from the lives of these men that they were good and faithful servants. Servants unto death, in fact. But they, as with many of us, had a concern with prestige and recognition. Jesus' teaching had not yet permeated their thinking to the point it had become a part of their own mindset. For them, as is no doubt the case with all of us, the concept of self-denial just did not come naturally. Looking out for one's self and not letting others run over us is engrained in most of us from an early age. Partly due to human nature and partly due to the teaching of society.
This engrained behavior, along with our own sin nature, is difficult to break. I find it one of the most difficult characteristics in myself to break. As a result, I will sometimes find myself almost obsessing over some perceived wrong by another. I mentally rehearse what I'm going to say to the one who "wronged" me in order to set the situation right. It is only after I have spent considerable time in these mental gymnastics that I realize what I am doing and begin to make it a matter of prayer. Envariably it is I who is set straight through the prompting of the Holy Spirit rather than me setting the other person straight. Too often, though, I have acted on my sense of injustice in such a situation out of emotions rather than out of prayer and spiritual guidance. When I have acted out of prayer and been prompted to "back off," I've never been sorry. Rather I have been thankful I did not act on my emotions.
Jesus had much to say about injustice, but His concern was more in defense of injustice toward others than that aimed at Himself. Is there a rule of thumb concerning injustice aimed at ourselves upon which we should take action? Not to my knowledge. Jesus' teachings often leave unanswered questions. We are not always pleased with this, preferring to have neat explanations and guildlines for everything. Following Jesus, however, is not about following a set of rules. Rather it is about a relationship with Him and functioning out of that relationship to respond to life as He guides us.