If, along the road, you chance upon a bird’s nest, in any tree or on the ground, with fledglings or eggs and the mother sitting over the fledglings or the eggs, do not take the mother together with her young. Let the motehr go, and take only the young, in order that you may fare well and have a long life. — Devarim/Deuteronomy 22:6-7 (JPS)
Plaut notes that this commandment is associated with a story concerning Acher [“the other one”], apostate rabbi Elisha ben Abuya (2nd Century CE). Below is the story, taken from Talmud tractate Kiddushin:
What did Aher see that made him go wrong? It is said that once, while sitting and studying in the valley of Gennesar, he saw a man climb to the top of a palm tree on the Sabbath, take the mother bird with the young, and descend in safety. At the end of the Sabbath, he saw another man climb to the top of the same palm tree and take the young, but let the mother go free; as he descended, a snake bit him and he died. Elisha exclaimed: It is written, “Let the mother go and take only the young, that you may fare well and have a long life” (Deut. 22:7). Where is the well-being of this man, and where is the prolonging of his life? (He was unaware how R. Akiva had explained it, namely, “that you may fare well,” in the world [to come], which is wholly good; “and have a long life” in the world whose length is without end.) — found in Bialik & Ravinitzky, based on Kid 39b
Plaut explains that, “through the story of Acher, the command concerning the bird’s nest became a focal point of discussion on biblical theology.” The Rabbis on-going relationship with their apostate colleague is fascinating in its own right — another, somewhat related, path to follow.
The tale above is part of a longer piece about Acher presented in Sefer Ha-Aggadah [Book of Legends]. Additional stories, taken from a variety of Talmudic and later midrashic sources, appear in this collection — comprising, in fact, an entire section, “R. Meir, Elisha ben Avuyah (Aher), Beruriah (fl. ca. 130-160 C.E.).” Plaut also cites Milton Steinberg’s fictional account of ben Abuya’s life, As a Driven Leaf NY: Behrman, 1939.
Complete citations can be found in Source Materials.