In 1907, Rabbi Sholom DovBer of Lubavitch was staying in Würzburg, Germany, and a group of chassidim came to spend a Shabbat with the rebbe. Among them were Reb Yosef Yuzik Horowitz, his son-in-law Reb Feivel Zalmanov, and Reb Elimelech Stoptzer.
The rebbe prayed for many hours that Shabbat morning, as was his manner. In the meantime, the chassidim recited kiddush and consumed a quantity of l’chaims. Later, when the rebbe had finished and they sat with him to the Shabbat meal, Reb Yosef Yuzik asked:
“Rebbe, what is a chassid?”
Replied the rebbe: “A chassid is a lamplighter. The lamplighter walks the streets carrying a flame at the end of a pole. He knows that the flame is not his. And he goes from lamp to lamp to set them alight.”
Asked Reb Yosef Yuzik: “What if the lamp is in a desert?”
“Then one must go and light it,” said the rebbe. “And when one lights a lamp in a desert, the desolation of the desert becomes visible. The barren wilderness will then be ashamed before the burning lamp.”
Continued the chassid: “What if the lamp is at sea?”
“Then one must undress, dive into the sea, and go light the lamp.”
“And this is a chassid?” Reb Yosef Yuzik asked.
For a long while the rebbe thought. Then he said: “Yes, this is a chassid.”
“But Rebbe, I do not see the lamps!”
Answered the rebbe: “That is because you are not a lamplighter.”
“How does one become a lamplighter?”
“First, you must reject the evil within yourself. Start with yourself: cleanse yourself, refine yourself, and you will see the lamp within your fellow. When a person is himself coarse, G-d forbid, he sees coarseness; when a person is himself refined, he sees the refinement in others.”
Reb Yosef Yuzik then asked: “Is one to grab the other by the throat?”
Replied the rebbe: “By the throat, no; by the lapels, yes.”