He is best remembered for a series of homilies on parshah (weekly Torah portions) that were delivered almost every Shabbat during the time he spent with his students in the Warsaw ghetto between the years 1939 and 1942.

As such, he was present at the birth of Polish Hasidism, and studying and working alongside the Seer of Lublin, Yisroel Hopstein, and Rabbi Menachem Mendel of Riminov.

Thus, there is an established and unbroken lineage, from teacher to student, linking Rabbi K. Szapiro back to the Elimelech of Lizhensk and his twin brother Zusya, who were the earliest promoters of chasidism, having studied with the Maggid of Mezeritch, grandson of the Ba'al Shem Tov who is said to have received the Lurianic Kabbalah from the place of its composition in Israel and transmitted it to the Jews of Eastern Europe.

He invested enormous efforts in maintaining Jewish life in the ghetto, including arranging for mikveh immersions and kosher marriages.

The book, which is a compilation of weekly sermons to his students, contends with complex questions of faith in the face of the mounting suffering of the Jews in the ghetto.

When it became apparent to Rabbi Szapiro that the end of the ghetto and all its inhabitants were near, he transferred this book and other manuscripts to the Ringelblum "Oneg Shabbat" Archive.

The book, originally simply entitled "Torah Innovations from the years 5700-5702," was published in Israel in 1960 under the title *Esh Kodesh* ("Sacred Fire").

Rabbi Kalman Menachem resides in Ramat Beit Shemesh, Israel and leads Congregation Aish Kodesh,[7] which is both a synagogue and the worldwide headquarters for spreading the teachings of his great-uncle.

[3] Isaac Hershkowitz: Rabbi Kalonymus Kalmish Shapiro, the Piasechner Rebbe: His Holocaust and pre-Holocaust Thought, Continuity or Discontinuity?, M.A.

Moshe Weinberger: "Warmed by the Fire of the Aish Kodesh: Torah from the Hilulas of Reb Kalonymus Kalman Szapiro of Piaseczna", Adapted by Benjamin Wolf.