The conjecture of Rabbi Avitzinsky. According to him, it appears that he first served as rabbi in Shkud and Hasenpoth (since in the communal register of Shkud his signature is found from the year 5520, signed as “the community of Shkud and Hasenpoth”), and afterward served as rabbi only in Hasenpoth, and his proof is from the fact that in Noda BiYehudah, responsa section 60, in a response from the year 5530, it is written to him only as “Av Beit Din of the community of Hazin- poth.” However, this is not proof, since in his approbation printed in the book Korban Reishit (Frankfurt a.M. 5538), dated Erev Shabbat, 26 Tishrei 5532, he signs “here in the community of Berlin… residing in Berlin with [his authority spread over] the communities of Shkud and Hasenpoth and the province of Courland, may it be preserved.” So too in the approbation for the book Mar'eh Kohen (Frankfurt a.O. 5536), dated 5 Nisan 5532, he signs “with [authority spread over] the communities of Shkud and Hasenpoth and the province of Courland,” and likewise in the title there it is written “Approbations of the great rabbi Moharar Aharon Levi Horowitz, Av Beit Din of the community of Shkud and the province of Courland,” and as noted below in the body text, even after his death he was still called “R. Aharon from Hasenpoth.”

In the collection Kerem Shlomo, year 18, issue Tammuz–Av 5755, p. 7, note 1, it is noted that in the year 5528 he was accepted as Rav-Av Beit Din of Berlin, and passed away there on Yom Kippur 5539, and his resting place is honored; but no source is cited there. And one should note from the responsa Besamin Rosh, Kise DeHarsena (Berlin 5553), section 37: “The rabbi, our master Aharon from Hasenpoth, of blessed memory, head of judges here for more than twenty-five years,” and according to this, he was accepted in Berlin as head of judges no later than the year 5513. And if so, it is clear that even after he was accepted as Rav-Av Beit Din of Berlin, he continued to sign as Av Beit Din of Shkud and Hasenpoth, as above.

First edition, Even HaEzer, sections 5, 60, 90, and additional responsa, as noted in the article of Rabbi Baruch Oberlander in the collection Or Yisrael, issue 55, p. 74, note 76. See more about him there and in notes 76–77.

Teshuvat Maharal, p. 269 ff. She'elot uTeshuvot Or HaShanim, section 4.

Otzar HaSefarim by Ben Ya'akov. Toldot Yeshivat HaYehudim BeCourland, second edition with additions and corrections. Rabbi Avitzinsky writes that a Passover Haggadah was printed under his name, titled Ma'aleh Beit Chorin with a commentary Mateh Aharon on Chad Gadya – Białystok, 5566. But this is an error, since this Haggadah was only printed, as appears on the title page, “at the home and press of the rabbi, our master Aharon Halevi Horowitz,” who is the printer and is not related at all to the aforementioned rabbi.