When a dispute in the Talmud remains unresolved, or a final ruling cannot be reached, the narrative simply concludes with the word "teiku," usually translated as “let it stand." There are, however, a number of other interesting explanations (“al derech hadrush”) of what this word means.

The most popular explanation of the word teiku is that its letters are an acronym for the words "tishbi yetaretz kushiot u’vayot," meaning, “Tishbi [another name for Eliyahu Hanavi] will resolve all questions and queries.”[1] According to another approach, the word "teiku" is related to the word "tik," meaning "a pouch," implying that the resolution to the dispute is hidden in “a pouch” and unknown. It is also suggested that teiku derives from "ishteku" (silence), as if to say that no one knows the answer. Finally, some explain that teiku is short for "teikum" --"let it remain unanswered.” Whenever a Talmudic dispute concludes with “teiku,” the halacha generally follows the stricter opinion if the matter is of a biblical nature, and the lenient opinion if the matter is of a rabbinical nature.

Rav J.B. Soloveitchik once asked his father why the Talmud sometimes left problems unresolved, merely concluding with teiku. In his words:

My father explained to me that a Jew must apprehend that he cannot understand and comprehend everything. When a Jew learns that there are halakhot which are ambiguous, then he will also come to the realization that there are other areas that are also not clear-cut. In matters of faith, teiku will also be encountered. The greatness of Abraham, our forefather, was that he knew how to say “Here I am” [Genesis 22:1] even though he did not understand the request that God made of him. The basis of faith is teiku. If a Jew does not master the concept of teiku, then he cannot be a true believer. It would not hurt if the rabbi possessed the courage and resoluteness to admit to teiku. The rabbi must not be ashamed to declare that he must refer the question to greater experts on the topic.[2]

Returning to the first, and most popular, explanation of the word “teiku,” the commentators ask why it is specifically Eliyahu who will be the one to settle all the unresolved Talmudic disputes. When Eliyahu returns to this world, with the arrival of Mashiach and the resurrection of the dead, all the other great sages and leaders will return, as well. As such, why wasn’t Moshe Rabbeinu assigned with the task of settling the unresolved Talmudic questions? It would certainly make sense for him to do so, as his life mission was transmitting Torah to the Jewish people! Some other great Talmudic scholar, perhaps? Why does the job go to Eliyahu?

Among the answers offered to this question is that the difference between Eliyahu and Moshe Rabbeinu is that Eliyahu Hanavi “never died.” We are taught that Eliyahu was one of the few individuals[3] who ascended to heaven alive, and that he continues to interact with this world to this day. Indeed, we are told that he comes to every brit mila and Pesach Seder. He interacts with us and is aware of our situation. It is explained that only someone who is familiar with the current realities and challenges that the Jewish people face can be qualified to issue far reaching halachic decisions that affect the entire nation. As great as Moshe Rabbeinu was, he has been “out of touch” with the Jewish people for quite some time. Another answer offered is that Moshe Rabbeinu's job was to receive and transmit the Torah to the Jewish people. However, the responsibility of interpreting and adapting the Torah to the realities of the day can be assigned to any competent scholar.

It is interesting to note that Eliyahu is referred to in three different ways: Eliyahu Hanavi, Eliyahu Hatishbi, and Eliyahu Hagiladi. “Hanavi” refers to Eliyahu in his role as a prophet, especially as it applies to his role in heralding the arrival of Mashiach.[4] "Hatishbi" is intended to correspond to the word "tashiv," meaning “to return,” referring to Eliyahu’s role as the one who will arouse and inspire the Jewish people to repentance.[5] Finally, "Giladi" is another name for the lishkat hagazit, the chamber in the Beit Hamikdash where halachic matters were decided, referring to Eliyahu's role in deciding halacha. Others suggest that "Hagiladi" refers to the village where Eliyahu lived, in Gilad, in Northern Israel.

[1] Tosfot Yom Tov, Eduyot 8:7.

[2] The Rav: The World of Rabbi Joseph B. Soloveitchik, vol. 1 p. 62

[3] Others who ascended to heaven alive include: Serach (the daughter of Asher), Chanoch, Eliezer (the servant of Avraham), Batya, and several others.

[4] Malachi 3:23.

[5] Malachi 3:24.