Son of Rav Yosef Yuzpa Katz
He was a disciple of Rav Yeshaya Segal Ish Horowitz Av Beis Din Frankfurt and Pozna. He served as Av Beis Din Dormstadt and after תמ"ח he served as Av Beis Din and rosh yeshiva in the bais medrash ha’gadol of Frankfurt.
After his father-in-law, Rav Shmuel Chaim Yeshayas, passed away on תס"ד, he served as Chief Rabbi of Frankfurt in all matters until the year תס"ו when this position was then assumed by Rav Naphtali HaKohen, the author of Semichas Chachamim (who held the position until .)תע"א
He was also author of the sefer Kos Yeshuos which was miraculously saved from fire that same year. On the 24th of Teves tragedy struck and a great fire raged through Frankfurt consuming over five hundred homes along with all their possessions and countless seforim. The fire lasted 24 hours and amazingly, the Maharshashach’s sefer, Kos Yeshuos, was recovered unharmed from the blaze. This, he describes in that sefer’s introduction.
The 24th of Teves was established in Frankfurt as a fast day to mourn the tragedy of the great fire, and the Maharshashach authored Selichos to commemorate the conflagration. (Some people fabricated a story accusing Rav Naphtali Kohen, of being responsible for the fire. Their claim was that he did this to prove his mastery over the angels, but then, mistakenly summoned the angelic Prince of Fire instead of the angelic Minister of Water to put it out. The homeless masses believed the tall tale and even though his name was cleared, he left for Prague in order to distance himself from the episode. Interestingly, Rav Naftali Kohen passed away on the same date as the fire: the 24th Teves around eight years later in Constantinople en route to Eretz Yisroel.)
The next rav was Rav Avraham Broda, author of Aishel Avraham, and after he passed away in תע"ז, he was succeeded by the author of Shu”t Shev Yaakov, Rav Yaakov Kohen. In between each rav’s appointment, the Maharshashach faithfully served as interim Chief Rabbi, paskening, answering all halachic queries and faithfully leading Frankfurt’s people. (See Chut HaMeshulash pp. 18-19)
The Maharshashach passed away on the night of Shabbos Kodesh Chai Tammuz תע"ט laid to rest in Frankfurt.
