If my intention is to set him straight and stop him from doing a terrible sin, I will almost certainly fail. The only intention that fits the role of a successful mochiah is: “This is my friend; I am concerned for his good.”
If I am looking out for kavod Shamayaim, or if I am a do-gooder concerned for the betterment of the world, my words will accomplish the exact opposite of their intended purpose. I won’t succeed in separating my friend from the sin; I will only succeed in separating him from me. The first requirement for the proper fulfillment of tochachah is that it must be out of love and concern for my friend.
The second condition for tochachah to be effective has to with the way it is delivered.
Do You Shout When You Put on Tefillin?
The Chofetz Chaim was once approached by a certain community leader who complained that no matter how much he reproached the people of his town, they didn’t listen. The Chofetz Chaim asked this person to describe how he went about rebuking his townspeople. The man described his method of yelling fiery words at them. The Chofetz Chaim asked him, “Tell me, when you put on tefillin, do you shout and carry on? Why do you feel the obligation to do so when you do this mitzvah?”
One of the most basic concepts of human relations is that people hate criticism. We hate it worse than poison, and we avoid it like the plague. When you criticize me, I become hypersensitive. If you whisper, I hear it as loud speech, and when you speak quietly, I hear it as if you are shouting in my ears. Being aware of this is vital in choosing the method, tone, and words with which I approach my friend. The mitzvah of tochachah is to help my friend improve. Without a strategy that is sensitive to human nature, even the best of intentions will backfire. To succeed in this mitzvah, I need to choose my words very carefully, making sure they are as soft and non-offensive possible. This is the second requirement of the mitzvah.
The reality is that this is a very difficult mitzvah to perform correctly. Typically, we find ourselves either not wanting to get involved or saying things that cause more harm than good. But when the driving force in doing this mitzvah is concern for the good of our friends, and we carefully study human nature and choose our words guardedly, Hashem will help us to perform it properly.