Rav Dov Ber, the Maggid of Mezritch, was born in Lukatch to Rav Avrohom. He was descended from Rav Hai Gaon and Rav Yochonon HaSandlar, a descendant of Dovid HaMelech. Rav Dov Ber learned with the Pnei Yehoshua in Lemberg early in his life. In 1752, he became the Ba’al Shem Tov’s closest talmid. Among his students were the Rebbe Reb Shmuel Shmelke HaLevi Horowitz and his brother, Rav Pinchas HaLevi Horowitz, the Baal Haflo’a, the Rebbe Reb Zusha and his brother, Reb Elimelech of Lizhensk, Rav Levi Yitzchok of Berditchev, Rav Nachum of Chernobyl, Rav Shneur Zalman of Liadi. His son was Rav Avrohom HaMalach (1740–1776). The classic anthologies of his teachings are Likutei Amarim, Torah Ohr, and Ohr Ho’Emes.
Rav Mottel of Slonim told in the name of the Chortkover: “When my Zeide, the Maggid, was at the end of his life, he placed his hand in front of a candle and we all saw, his hand was so translucent and clear that we could see the flame through his hand! His body was so pure and refined that it was as if it were clear.” The Chortkover explained, “The Tzaddikim drew their physical bodies after their souls and only when they could push them no further, they relented.” (Maamar Mordechai 17)
When the two holy brothers, Rav Shmelka of Nikolsberg and Rav Pinchas, mechaber of the Haflo’a, visited the holy Mezritcher Maggid for the first time, the Maggid gave them a description of the entire avoda of a Jew during his entire lifetime and what it should consist of.
He told them that even after serving Hashem in such a lofty manner, still, if afterward one felt that he had actually accomplished something, this arrogant pride causes the entire avoda to be cast aside! (Nesivos Sholom, Vayera)
