The Mishnah in Maaser Sheini 5:4 discusses the obligation to be finished with all maaser by the Pesach after the third and sixth years of the shemittah cycle. The mishnah describes messages sent to remind people to remove the maaser from their crops, so that can give it out or destroy it before the deadline. The Yerushalmi (31b) opens the discussion of the mishnah wondering why the obligation to be able to say “I destroyed the qodesh from the house…” would obligate one to do anything to untithed crops, called tevel. The Gemara quotes R’ Hila repeating Shemuel’s answer, “זאת אומרת שהטבל קרוי קודש — this tells [us] that tevel is called qodesh.”

Think about this… Tevel, the farmer’s raw produce, is considered holy. Terumah and maaser don’t become holy, they are the separated-out portions of holiness inherent in the pre-tithed tevel, separating them so that the owner may eat the remainder. Just farming Eretz Yisrael creates holiness in the product.

The word in Hebrew closest to “secular” is “chol”. The root is the same one used for chal, as in the first mishnah of Megillah, where the mishnah discusses the dates on which the megillah is read, depending on which day the 15th of Adar, Purim, falls out — chal — upon.

Chol is a blank slate. One we can write holiness upon. Qedushah means separation. As Chazal comment on the verse (quoted by Rashi), “‘Qedoshim tihyu’ perushim tihyu — ‘You shall be holy’ — [meaning,] you shall be separate“. But not separation from, but separation for. The farmer doesn’t create holiness by refusing to farm and leading a guru’s life atop the mountain. He does it by taking his farming and using it to develop G-d’s land.

Similarly, when Yaaqov fled from Esav, he risked returning back to get some “small jugs”. Rashi again quotes Chazal, saying “Tzadiqim cherish their possessions more than their own lives, because they avoid sinning through thievery.” As I wrote on that concept and the Yalqut Reuveini who ties it to other events later in history:

Proper business ethics isn’t “just” the permissable way to conduct business, it actually sanctifies the activity. And therefore, the pachim qetanim were sacred to Yaaqov, not to be simply left behind.
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Which brings us to Chanukah…. The Jews lost themselves to Hellene values. To a religion where even the gods represent physical forces: Ares was the god of war, Hermes was the concept of change, Venus of love, etc…

And then they find the jug of oil. The jug of holy wordliness, of sanctifying the universe through halakhah. Not disdain for the physical or the beautiful, but knowing its value — as a tool. And with that concept the Chashmonaim revived Jewish loyalty, disbanded Hellenist oppression, and restored the concept of Jewish autonomy for the next two centuries….