In the Gemara’s famous account of the Chanukah miracle (Shabbat 21b), it tells that after the Jews’ victory over the Greeks, the Chashmonaim “searched and found only a single cruse of oil placed with the seal of the kohen gadol.” The conventional understanding of this description is that the kohen gadol’s seal was necessary to verify the oil’s status of purity, that it was suitable for the kindling of the menorah. Some writers, however, questioned this reading, noting that there does not appear to be any halakhic reason for such a seal. It seems unlikely that all the materials offered in the Temple had to be kept in special seals that attested to their status of purity. The question thus arises as to the significance of the kohen gadol’s seal on the single cruse of oil found by the Chashmonaim.
Rav Aryeh Leib Breslau, in his Penei Aryeh (40), cites a creative approach to explaining this account in the name of Rav Avraham Lifshitz, which was shown to him when he became rabbi of Rotterdam. Rav Lifshitz understood that the phrase “the seal of the kohen gadol” as suggesting that the oil was associated specifically with the kohen gadol; meaning, this was his personal oil. He explains that the kohen gadol was required to offer each day a special meal offering – the minchat chavitin – which was to be fried in oil (Vayikra 6:12-16). Possibly, then, the oil which the Chashmonaim found upon searching through the Beit Ha-mikdash was the oil which the kohen gadol had prepared for his daily mincha offering.
The question, then, becomes why the kohen gadol placed his seal on the cruse containing his oil. Additionally, we need to understand why the Chashmonaim assumed that this oil was suitable for the menorah. The Mishna in Masekhet Menachot (86a) establishes that only the highest quality oil may be used for the kindling of the menorah, whereas the oil used for the mincha sacrifices did not have to be of such pristine quality. Why, then, did the Chashmonaim use the kohen gadol’s oil, which was earmarked for his daily mincha, for the kindling of the menorah?
Rav Lifshitz explained that the kohen gadol at the time took it upon himself to use only the highest quality oil for his daily minchat chavitin. The Gemara (Menachot 86b) comments that the reason for the difference between the required standards for the menorah and the mincha offerings is “ha-Torah chasa al mammonan shel Yisrael” – the Torah’s laws must not result in the nation’s impoverishment. The daily kindling of the menorah did not require a large amount of oil, and thus it was not unreasonable for the Torah to demand only the highest quality oil for this mitzva. Demanding this standard every time a mincha offering was brought, however, would be financially burdensome, if not crippling. Rav Lifshitz deduced from this line of reasoning that there was value in an individual choosing to adhere to the highest standards when offering his mincha. It appears from the Gemara that as a matter of regular policy, it was impractical to demand the highest quality oil for menachot, but in principle, this standard is appropriate for the menachot, albeit not strictly required as it is for the menorah. Accordingly, it is possible that the kohen gadol at the time of the Chanukah miracle strove to perform his obligation of minchat chavitin at the highest standard, ensuring to use the same quality oil as is required for the menorah. To that end, he kept his oil in special sealed jars, designating it especially for his mitzva.
It has been suggested that this approach might explain the reason for the different standards that Chazal assigned to the mitzva of the Chanukah lighting. Although the basic obligation requires just a single candle each night, the universally accepted custom is to adhere to the “mehadrin min ha-mehadrin” standard, whereby we add a candle each night of Chanukah. The miracle of the oil was made possible by the fact that a kohen gadol strove to adhere to the highest possible standards of mitzva observance. It was because a supply of highest quality oil was designated for the minchat chavitin that the Chashmonaim were able to light the candles which then miraculously burned for eight nights. We commemorate this aspect of the miracle by fulfilling the mitzva of Chanukah candle lighting at the highest possible standard, rather than feel content by satisfying the basic requirement.