There is only a simple litmus test to determine if you are a master or a slave! Do you act or do you react? Most of us react like a slave, and expect to be a master. It is like somebody wanting to reach the east, walks towards the west, and complains that he did not reach the east! Always examine your own behavior, and remind yourself that you are a master who takes actions and who does not react like a yoyo. When you react, anybody can make you a slave, as you are dancing to their tune. Regardless of the circumstances, you act like a master, acting on your own volition. Once you start acting on your own volition, other people cannot make you a victim of your weakness of reacting.
Sometimes friends ask me, "Gopi, how will I act if somebody is using words to insult me?" My reply is, "Anybody can say anything to me, but he cannot insult me without my permission." Only when you accept what others are telling as true, you are insulted. Otherwise, it is their opinion, you do not have to make it your reality! For example, if somebody tells me, "Gopi, you are an idiot". I say, "Thank you very much!" I did not react, I simply acted on my own volition. It is his opinion that I am an idiot. But I do not take it as true, and it does not affect my state of mind at all.
There is a simple technique that can save you under all circumstances, without reacting. Simply say under those circumstances, "I am grateful for the experience," and wish the other person well. Many times, when we react it becomes spontaneous, and it can upset you and make you lose your composure. But, if you have already cultivated the habit of gratitude, it will guard against all of those useless reactions, and make you a master even under the most trying circumstance. Always ask this question of yourself, "Do I want to be a Master of my Emotions, or a slave of my emotions?"