An anecdote concerning Louis Ginzberg and his close friend Alexander Marx (who was the disciple and son-in-law of R. David Zvi Hoffmann, in addition to being the world class librarian that he was):
From the age of twenty-one when he earned Semikhah-the right to judge under Jewish law--until his death at the age of eighty, Louis Ginzberg devoted considerable time and effort to this task. He never held a position in the Jewish community which would have required him to decide matters of law, as was the duty of an active rabbi or a member of the law courts; Louis Ginzberg's concern with law had a different origin and motivation.
As knowledge of his reputation as a talmudist spread, those who wanted to know the law on any difficult issue sought his opinion. His major decisions were in the nature of advisory opinions, although he was drawn into a few cases where active conflicts raged, usually between an individual or group of individuals and the rabbi or the board of directors of a congregation.
His legal opinions covered a wide range of subjects, including those on which he could bring his sense of humor to bear. He was fond of telling the story of being asked by his colleague Dr. Marx, shortly after the latter's arrival in this country, whether one was permitted to use an elevator on the Sabbath. My father replied that it was not permitted, and Marx started his climb of six stories. My father, always restive when confronted with the rigidities of German orthodoxy, awaited the return of the elevator to the ground floor, stepped in, and rode up. Marx, astonished, reminded him that he had just stated that using an elevator was not permitted. He replied: "I didn't ask for an opinion!"
Eli Ginzberg (his son) published the text of a letter his father received while on vacation in 1948, a letter which greatly disturbed him.
Levi of Neistadt:
Your life has been a failure. Not only have you made the Torah a Kardom Lachpor Bo, and you glory in the designation of Professor of Talmud and great authority on "Halakhah," when you know that there are scores of men superior to you in Talmud in this city; not only have you helped produce "Rabbis" who are in almost every single case Boale Niddot and Chot'im and Machti'im et Harabim; not only are you a Poresh Min Hatzibur of the real Talmidei Chachamin who toil for the welfare of Klal Yisroel; but you have cast aspersion on the Talmud and supported the Kofrim: you declared at least twice (once in your Legends and once in your Students, etc.) that the Rabbis of the Talmud uttered their Hagadic statements on the spur of the moment (May the Almighty forgive you), and you support Weiss in his denial of the authenticity of a great part of Torah Shebdal Peh. Your works are full of echoes of the Kofrim. Remember your childhood hopes, and now see yourself not only as an associate of M. Kaplan (Yimach Sh'mo) but also in part responsible for him and for others like him. For you, the authority, have undermined the faith of these Am Ha'aretz. May the Almighty open your eyes and help you to recant, to recall the harmful books, to repudiate your associates the Kofrim, and to return to the Tzibbur of Talmide-Chachamim.
Eli Ginzberg relates that this letter greatly upset his father and "within twenty-four hours he had a severe case of herpes zoster (shingles), and although the acute infection subsided after a time, he was left with an aggravated neuralgia which plagued him every day and night until he died."
Eli Ginzberg, Keeper of the Law : Louis Ginzberg, 1st ed. (Philadelphia: Jewish Publication Society, 1966) pp. 214-215 & 265-266