R Yehuda said that R Asi said that Rav said: It is prohibited to count money opposite a Hanukkah light. R Yehuda relates: When I said this before Shmuel, he said to me: Does the Hanukkah light have sanctity that would prohibit one from using its light? R Yosef strongly objected to this question: What kind of question is that; does the blood of a slaughtered undomesticated animal or fowl have sanctity? As it was taught in a baraita that the Sages interpreted the verse: “He shall spill its blood and cover it with dust” (Vayikra 17:13): With that which he spilled, he shall cover. Just as a person spills the blood of a slaughtered animal with his hand, so too, he is obligated to cover the blood with this hand and not cover it with his foot. The reason is so that mitzvot will not be contemptible to him. Here too, one should treat the Hanukkah lights as if they were sacred and refrain from utilizing them for other purposes, so that mitzvot will not be contemptible to him.
In principle, we must distinguish between tashmishei kedusha– items that have inherent sanctity – like the vessels used in the Temple, a Torah scroll, phylacteries, and the like, and tashmishei mitzva – those items that are used simply to perform a mitzva. The principle is as follows: Sanctified items no longer in use maintain their sanctity and must be buried. However, items used to perform a mitzva may be discarded. The Ramban explains that on that basis, Shmuel expressed surprise when the Gemara insists that Hanukkah lights be treated with the level of respect usually reserved for sacred items. Rav Yosef answered that while a mitzva is still being fulfilled, one must treat the items used for the mitzva with added deference, despite the fact that they do not retain their sanctity after the fulfillment of the mitzva.