We read in Parashat Toldot that when Yitzchak was compelled to move to the Philistine region due to the drought conditions in Canaan, God appeared to him and reaffirmed the promises He had made to Avraham. God concluded the prophecy by saying that these blessings were granted “on account of the fact that Avraham heeded My voice and observed My charge, My commands, My statutes and My laws” (26:5).
The Gemara, in Masekhet Yoma (28b), interprets this verse to mean that Avraham observed all the Torah’s commands. In fact, the Gemara adds, not only did Avraham observe all the commands written in the Torah, he even observed the mitzva of “eiruvei tavshilin,” which does not actually appear in the Torah.
At first glance, the law of “eiruv tavshilin” is mentioned here simply as an example of a halakhic detail which we would not have expected Avraham to observe. Not only is it not written in the Torah, it was introduced by Chazal. Seemingly, then, the Gemara is telling us that Avraham intuited and observed the entire corpus of Halakha, including those rules established by the Sages millennia later.
On a deeper level, however, many have sought to identify the possible significance of this specific reference to the law of “eiruv tavshilin.” This law involves the preparation of food for Shabbat when it is immediately preceded by Yom Tov. The Mishna in Masekhet Beitza (15b) establishes that although one may not cook on Yom Tov in preparation for Shabbat, one may begin cooking for Shabbat before Yom Tov and then continue on Yom Tov. Therefore, when Yom Tov falls on Friday, we prepare two food items for Shabbat before Yom Tov, which then allows us to make preparations over the course of Yom Tov for Shabbat. What might be the particular significance of this law in the context of Avraham’s mitzva observance? What reason could there be for Chazal to specifically point to “eiruv tavshilin”?
One answer, perhaps, emerges from the Gemara’s formulation (there in Masekhet Beitza) in explaining the concept of “eiruv tavshilin”: “Zokhreihu mei’achar she-ba le’hashkicho” – “Remember it, since one is likely to forget it.” The Sages provided a means of circumventing the prohibition against preparing on Yom Tov for Shabbat because they wanted to ensure that people would not forget about and neglect Shabbat. When Yom Tov falls just before Shabbat, the special excitement and festivity surrounding Yom Tov might overshadow the observance of Shabbos, and lead to its neglect. Each Yom Tov is celebrated just once a year, while Shabbos is observed each and every week, and thus the special occasion of Yom Tov could easily dominate one’s time and thoughts at the expense of Shabbat. Chazal wanted to ensure that Shabbat would receive proper attention and consideration even when it is preceded by Yom Tov, and they therefore instituted the “eiruv tavshilin” to facilitate Shabbat preparations in such a case.
Symbolically, then, “eiruv tavshilin” represents the need to be mindful of our basic, routine obligations even amid the excitement surrounding special and exceptional mitzvot. This institution seeks to avoid the danger of neglecting ordinary responsibilities in favor of extraordinary undertakings. It reminds us to pay sufficient attention to “Shabbat” even during “Yom Tov,” to tend to our elementary duties even as we pursue loftier and more ambitious goals.
This message, perhaps, underlies Chazal’s reference to “eiruv tavshilin” in the context of Avraham’s mitzva observance. The Torah and Midrashim tell of Avraham’s extraordinary achievements, such as preaching monotheism, inviting wayfarers as his guests, waging wars against powerful armies, and nearly slaughtering his own son when commanded to by God. Chazal perhaps seek to remind us that Avraham also fulfilled the message of “eiruv tavshilin,” ensuring not to neglect his basic responsibilities amid his tireless pursuit of very ambitious goals. Although he devoted a great deal of time to “Yom Tov” – to extraordinary achievements – he remained forever mindful of Shabbat – his ordinary, elementary duties and responsibilities as a human being and a servant of God.
(A somewhat similar explanation is given by Rav Yaakov Moshe Charlap, in Ma’ayanei Ha-yeshu’a, p. 191.)