Na Nach Nachma Nachman Meuman

Na Nach Nachma Nachman Meuman (Hebrew: נַ נַחְ נַחְמָ נַחְמָן מְאוּמַן‎‎) is a Hebrew language name and song used by a subgroup of Breslover Hasidim colloquially known as the Na Nachs. The complete phrase is Na Nach Nachma Nachman Me'uman. It is a kabbalistic formula based on the four Hebrew letters of the name Nachman, referring to the founder of the Breslov movement, Rebbe Nachman of Breslov, along with a reference to his burial place in Uman, Ukraine.

In 1922, Rabbi Yisroel Ber Odesser, a Breslover Hasid, claimed to have received a petek (note) addressed to him from Rebbe Nachman, although the latter had died in 1810. The seventh line of this petek is signed Na Nach Nachma Nachman Meuman, which became Rabbi Odesser's personal meditation and song. Before he died, he taught this phrase to a group of devotees who formed the Na Nach movement.

Rabbi Moshe Feinstein may have been referring the petek in a letter, that he saw a "wondrous secret document which he possesses".

The Na Nach Nachma phrase was "revealed" and taught by Rabbi Yisroel Ber Odesser, a well known Breslov figure who was born in 1888 in Tiberias. Odesser was among the first Breslover Hasidim in Israel, having learned about the movement from Rabbi Yisroel Halpern when he was a young yeshiva student.

When he was 33 years old, Odesser was overcome with weakness and hunger on the Fast of Tammuz. He decided to eat. But immediately after eating, he felt great sorrow at having succumbed to his own physical temptations. After five continuous days of prayer, a powerful thought came to him: "Go into your room!" He obeyed the inner voice, went to the bookcase, and randomly opened a book. In the book was a piece of paper that he would later call "The Letter from Heaven." The paper, written in Hebrew with one line in Yiddish, read as follows:

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