I seem to remember a story about him putting a curse on Prague, and the city being destroyed by fire. (But I may have got it confused with another city and another Rabbi). If anyone can add details about his life I would appreciate it.
Here are the wikipedia article and a couple of stories I found on the web.
Rabbi Aryeh Leib ben Asher Gunzberg (aka Shaagat Aryeh) (Hebrew: אריה ליב גינסבורג) was born in Lithuania, c. 1700, and died at Metz, France June 23, 1785. He was a Rabbinical casuist often referred to by the name of his most famous book, Shaagat Aryeh (Hebrew, שאגת אריה, for 'Roar of the Lion').
At one time Gunzberg was Rabbi in Pinsk, and then later founded a yeshivah in Minsk. Here however he engaged in hostile dispute with the Gaon Yechiel Halpern, whose supporters eventually drove Gunzberg from the city.
His book ‘Shaagat Aryeh’ was first published in Frankfurt-am-Main in 1755 and is still frequently quoted in rabbinical debate, as are many of his responsa.
He became Rabbi in Metz in 1765, but an early argument with his congregation led to him refusing to enter the synagogue except to give four sermons a year. Despite this he retained his post until his demise.
Rabbi Aryeh Leib (The author of “Shaagat Aryeh”) lectured in the Beis Midrash of Minsk. He expounded deep thoughts, and uprooted mountains with his sharp reasoning. The scholars of the city who were present could not understand the depth of his rhetoric. When he finished his lecture, the heads of the community and scholars approached him to wish him “Yasher Koach” [2].
He told them, “What is said of the wise men of Minsk is greater than what is said about the angels of Heaven”.
The listeners were surprised.
Rabbi Aryeh Leib told them: “Is it not said about the angels of Heaven (Ezekiel 1, 7), and their feet are like the feet of a calf, but as for you, your heads are also the heads of calves…”
The Sha’agas Aryeh (R’ Aryeh Leib Ginsberg) was seventy years old when he was appointed Rav of Metz. Upon arriving in Metz, he heard that there were members of the community grumbling over the selection of such an elderly rabbi. “We should have appointed a younger Rabbi, one who will remain at the helm of our community for many years,” they said.
That Shabbat, the Sha’agas Aryeh gave his first drasha to the people. The Sidra that week was Vayigash and he quoted the verse above where Pharaoh asked Yaakov how old he was when he arrived in Egypt.
To this Yaakov answered, “The span of the years of my sojourning have been one hundred and thirty years, [but] the years of my lifetime have been short and harsh, and have not approached the years of my fathers lifetimes.”
There are a few questions we may ask about this exchange. First, why did Pharaoh want to know how old Yaakov was? Second, why did Yaakov feel the need to add “the years of my lifetime have been short and harsh?” Pharaoh did not ask for a description of his lifetime; why did Yaakov deem it necessary to provide him with one?
The Sha’agas Aryeh offered the following answer. “Pharaoh saw that the land of Egypt was blessed and that the famine ended as soon as Yaakov arrived. He realised that the new prosperity was thanks to Yaakov’s presence but he was concerned that it would not last, as Yaakov was apparently already old. This is why Pharaoh asked Yaakov, how old he was. Yaakov, however, understood why Pharaoh asked him that question, so he responded – ‘the years of my lifetime have been short and harsh’ – it may seem that I am very old and at he end of my life, but my years have actually been “short” compared to “my fathers lifetimes,” as they lived for one hundred and eighty years.’
“So why do I look so old?” asked Yaakov rhetorically to Pharaoh. “It is due to the fact that ‘the years of my lifetime have been short and harsh’ – ‘The stress of a difficult life,’ said Yaakov, ‘has made me appear older than I actually am.’
“The same applies to me,” continued the Sha’agas Aryeh. “The reason I may look well on in years is actually only because of the hardship and persecution that I have faced throughout my life. But I assure you, he concluded, that with Hashem’s help, I will serve as your Rabbi for more than twenty years.” The words of this great sage were fulfilled, as the Sha’agas Aryeh served as the Rabbi of Metz for over twenty years!
