The Mitzva of Ner Channuka is based on the vial of oil that was found untainted and with the unbroken seal of the Kohen Gadol, upon the return of the Jews into the Bais Hamikdash after defeating the Yevanim (Greek soldiers).
Every year on Channuka we say the beracha of “Sheasah Nissim La’avoseinu” when we light the menorah. The Pnei Yehoshua asks, we know there is a halacha of “Tumah Hutrah B’tzibur”, as the Chazzal explain on the Pasuk of “L’halos Ner Tamid” in Parshas Emor (that it would be permissible to light the menorah b’tumah), so why do we actually celebrate the fact that the shemen was untouched when it was not in fact a prerequisite to lighting the menorah?
Penei Yehoshau answers that the miracle itself was to actually show Klal Yisroel that Hashem was embracing them again with the original love and a love that has no boundaries…that even when it would have been permissible to use any oil, Hashem miraculously saved a special bottle for his beloved nation as an illustration of his special love for us.
Rav Pam Z”l, is his sefer Atara Lamelech, illustrates this love as follows: imagine a couple who are experiencing shalom bayis problems and who have grown to hate each other. They go to seek the counsel of a therapist who ultimately helps them find peace with one aother. However, in many instances, the original love and passion never fully returns. Not so with respect to our relationship with Hakadosh Baruch Hu. The minute that we return to Hashem, he embraces us with the original love and devotion. This was manifest in the miracle of Channuka, when Hashem went the extra step to provide us with an untainted vial of oil.
The Moadim Uzmanim B’halacha (Rav Moshe Shternbuch Shlita), asks an interesting question:
The gemorah in Shabbos daf Chaf Alef, asks, “Mai Channuka”…what is the basis of Channuka?
The gemorah goes on to describe in detail the miracle of the oil which the Jews discovered in the Bais Hamikdash upon their return to the Heichal. However, in the actual “al hanissim” which we say on Channuka in Shemona Esreh, we find that the focus is almost exclusively on the actual battle itself, where the undermanned Chashmonaim were able to vanquish the superior army of the Yevonim, and it is only at the end, that a small reference is made to the miracle of the oil. Why the discrepancy?
Rav Moshe explains that whereas the the story of the chag itself revolves around the battle between the Yvonim and Chashmonaim and our ultimate victory, this story in and of itself would not be cause for the enactment of the Holiday of Chanukka for all future generations. Indeed, there have been many battles fought and won/lost in the history of our people. There were instances where the victories have been miraculous as well. However, we have not enacted Yomim Tovim in these instances.
The reason for Channukka itself…where the Gemorah asks “Mai Chanukka” is a deeper question than the story of the conquest itself. The story of the conquest itself is indeed mentioned and appropriately referred to in the al hannisim which we say in our Shemona Esreh.
However, when the Gemorah asks “Mai Channuka”, the Gemorah wants to know why in this specific story, Chazzal enacted a Yom Tov for all future generations…and the answer which the Gemorah gives, is based on the Miracle of the shemen/oil, which was an illustration of Hashem’s tremendous Chiba-Love for Klal Yisroel.