One year before Simchas Torah many people passed before the Lubavitcher Rebbe to receive "lekach" - honey cake. One of the people was a hippy - long hair and all. When he reached the Rebbe, the Rebbe asked him "Where are you staying for hakafos?" The truth was that he wasn't planning to stay at all for Simchas Torah. He hemmed and hawed and the Rebbe told him that he really wants him to come and encouraged him to do so and the hippie moved on.
The next person on line was a Satmar Chasid. Satmar believes that outreach is dangerous and that one should insulate oneself from the general society. The Rebbe realized that this chossid didn't approve of what the Rebbe just did. He said to the chossid "Do you know why I invited this man? Do you know the sefer "Tehilla Li-dovid [of the first Satmar Rebbe, the Yismach Yisrael, Rebbe Moshe Teitelbaum]?"
The chossid said that he does. The Rebbe proceeded to tell him a story from the sefer. A yid named R' Yitzchak, the father of Reb Michel Zlotochover, came up to shomayim and was greeted by none other than Rashi. Rashi told him that he is greeting him in the merit of his holy son. Rashi asked what makes his son so special.
Reb Michel's father said that his son learns a lot. Rashi said that is very special, "talmud torah ki-neged koolam", but a lot of people learn a lot. R' Yitzchak said that his son doesn't eat during the day and only breaks his daily fast at night. Rashi said the this is very holy but a lot of people afflict themselves. R' Yitzchak said that his son is involved in pidyon shvuyim - redeeming Jewish captives. Rashi said that this is a wonderful mitzva but others are involved in this mitzva as well.
The Reb Michel's father said three words: ורבים השיב מעוון - He returned many people back from sin and brought them back to Hashem. Rashi said "That is it. That is what makes him so unique".
The Rebbe looked at the Satmar chossid and said "Farshteist?" [You understand?] The chossid answered "Ich farshtei zeiyer git...." [I understand very well].
That Simchas Torah the hippie was there at 770, dancing with everybody else.
ורבים השיב מעוון.