Our Sages tell us that the reason for the Destruction of the Second Temple and the Dispersion of our People among the nations was שנאת חנם – hatred without cause. And only אהבת חינם – love without cause – can bring about the rebuilding of the Temple and the end of our bitter Exile.
I know someone who took this truth to heart, and made a special effort to generate ahavat hinam (love without cause). When he would walk into a room, he would ask himself: "Can I find it in myself to respect and love each and every Jew in this room?" While this approach is certainly commendable, I don't think it can begin to solve our problem because its effect is likely to be limited. Most people would not be aware of what this individual is thinking. But if the question is modified slightly, I think that it could begin to create a revolution. Indeed, it is particularly appropriate during the "Three Weeks." The question we should be asking ourselves is: "How can I make everyone around me feel that I love them, or at least respect them?"
We tend to think that the way we can show people that we love them is by giving them presents or by doing them favors. But the truth is otherwise, as a wise man once said: "At the end, what we remember the most is not what someone did for us, but how they made us feel." How can we make those around us feel good? By taking a genuine interest in how they are doing, and by smiling at them. Our Sages see this hinted in the words of the Torah" ולבן שיניים מחלב ". As they put it: It is better to show the white teeth of a genuine smile than to give a cup of milk. ( .(:כתובות קיא
Unfortunately, we think that we are being especially nice if we smile at someone to brighten up their day. This is a big mistake. The truth is that we can actually mess up someone's day by greeting them without a smile. Thus, our Sages tell us that this is our responsibility not to welcome someone with a sour face. If we do so, we are doing the other party an injustice. Elsewhere, our Sages put the matter even more dramatically: If one were to give all the presents in the world with a sour face, it is as if he gave nothing. However if he accepts another with a smile, although he may not have given anything, it is as if he gave all the presents in the world." (Avot of R' Natan, end of Ch.13)
The reason is that when you accept someone with a smile, it shows that you value him and care about him. And that is the present everyone wants. A present is only a "token of appreciation," but a smile is appreciation itself.
Just the other day while I was on the way to morning prayers, a woman jogging with her dog passed me by. I could not help but notice her T-shirt: "No one understands me except for my dog!" It is no coincidence that the Hebrew word for dog is כלב , a word which hints at the dog's essence: כל לב all heart. The dog is "man's best friend," and probably the world's most popular pet because, when the owner comes home, the dog displays excitement to see him back. The owner feels the "heart" of the dog. It has not been proven if animals are capable of real emotions, but dog owners all swear that they are.
We should not be too proud to learn something from the dog. Smiling and showing excitement when we greet others is the way to make them feel good – and "understood." It is also an efficient way to melt senseless hate, and bind Jewish hearts together. Only then will we merit to see the Temple once again standing on its foundation.