Parashas Tzav begins with the mitzvah of terumas hadeshen, the daily removal of some ash from the sacrificial altar in the mishkan and later the mikdash. As mentioned by the Torah (Vayikra 6:4) and expanded upon by the Oral Tradition, the officiating kohen donned priestly garments when doing so albeit of lesser value than his usual ones (see Rambam, Hilchos Temidin uMussafin 2:10 and Kessef Mishneh ibid.) The kohen went to the top of the altar, scooped a shovel full of ash and placed it on the side of the mizbei'ach. Rashi (ibid.) already notes that a mound of ash (the tapuach) was present in middle of the altar. Only a small amount of ash was removed each day and only when the altar was overflowing with ash would it be cleaned out totally. (See further on for a debate concerning this last point.)
What is the meaning behind this mysterious mitzvah? Seifer HaChinuch presents a straightforward rationale; we honor the House of G-d by cleaning and maintaining it properly. But this does not explain why only a little bit of ash is removed each day. If the goal is cleanliness, should not all the ash be removed each day? Indeed, Rambam (ibid. 2:13) seems to maintain that outside of festivals, the entire mound of ash on the altar (the tapuach) was removed after the terumas hadeshen by other kohanim. But the initial removal of only part of the ash remains mysterious. Other Rishonim maintain that the whole mound was not removed unless there was no more room (see above Rashi and Mishneh Lamelech ibid.). The mystery thickens when we turn to a related mitzvah - that of hatavas hamenorah. Each morning and afternoon a kohein would clean out the menora from the previous days lighting (ibid. 3:10). This service requires a kohen (Hilchos Bias Mikdash 9:5) as does the terumas hadeshen (ibid. 9:8), but the most famous of avodos, the lighting of the menorah itself, is valid if done by a zar, a non-kohein. Rambam (ibid. 9:7) even maintains that it is not only valid ex post facto, if done via a zar, but he may light it initially! (See Ra'avad ibid.) All these anomalies certainly require study.
I once heard from Rav Noach Isaac Oelbaum shlit"a in the name of sifrei chassidus that the main component of the avodash hamenorah was the hatava, the cleaning out, for this represents the elimination of bad qualities or insufficient or impure aspects of Divine service. A person should constantly strive to climb ever higher in his avoda, never satisfied with his current level, but he also must endeavor not to be discouraged by failures in his efforts. Every day is an opportunity to do hatavas hamenora, to clean out the past failures and start fresh. Once this is done, avodas Hashem is much easier as represented by the fact that the hadlakas hamenora does not even require a kohen. The harder part of the work is eliminating deficiencies. An oft-quoted comment of the Vilan Gaon states, "It is easier to learn the entire shas then change one midda ra'ah (bad quality)!" This is the higher avoda as indicating by the fact that it requires a kohen. Perhaps the same approach can be given to explain one meaning behind the daily terumas hadeshen. Had the Torah merely required removal of the ash of the mizbei'ach, this might lead to the erroneous impression that the cleaning is not an act of Divine service but is merely a hechsheir mitzvah, a preparatory act, for that day's korbanos. (See Rav Shimshon Rafael Hirsch where he makes a similar distinction although he explains the terumas hadeshen in an entirely different, insightful way.) The requirement of priestly garments for this service further underscores that this too is an act of avodas Hashem.
The incense altar was also cleaned every day; this cleaning was called dishun mizbei'ach hapenimi (Hilchos Temidin uMussafin 3:4 ff.). This too requires a kohein (see Hilchos Bias HaMikdash 9:8). Much has been written by the commentaries distinguishing between the role and symbolism of the various vessels of the Temple. The incense altar, the outer altar and the menora all symbolize different aspects of Divine service. One approach opines that the incense altar represents the service the soul, the outer sacrificial altar the service of the body, (see Keli Yakar on Shemos 30:1) and the candelabrum the study of Torah, specifically Torah sheb'al peh. Once can suggest that each aspect requires a hatava or a dishun, a constant self-analysis of how each of these aspects of Divine service can be improved. This approach could help explain one aspect of the significance of these aspects of the Temple service.
Torah was given to klal Yisrael not just to individuals. The phenomenon of "as one man with one heart" at Mount Sinai was not just a statement of Jewish unity, but a necessary prerequisite for the giving of the Torah for it was a gift to the Jewish people not just to each person individually. We are, to quote Rav Hirsch and Rav Soloveitchik, "a covenantal community" which is charged to bring the truth of G-d and His teachings to the world. Consequently, so much emphasis is placed on ahavas Yisrael, interpersonal relationships and communal service. But in order to be a more perfect member of this great community and to be able to more fully serve its other members, each individual also needs to strive to become a better person and Jew. When asked whether Yeshiva students should spend more time on kiruv and less time in Yeshiva, my Rebbe, Rav Aharon Lichtenstein zt"l, answered, "The Jewish people don't need half-baked potatoes!" The more knowledgeable you are, the better you can serve the community.[1]
The worldwide spread of disease currently raging (Hashem yatizleinu b'karov!) and the almost global quarantine-like conditions (whether actual or virtually so) can give an opportunity to engage in self-introspection, in the mitzvos bein adam l'atzmo (between a man and himself); to engage in a terumas hadeshen of sorts which is a precious aspect of avodas Hashem. The inability to engage in communal prayer, a central feature in tefila, should be utilized to perfect our kavana and length of our prayers; in a word, to improve our communication with Hashem. To be sure, opportunities to help other people in need abound, and one should certainly take advantage of them, but one should also strive to become a better person in their internal self. News articles have been publicized that domestic violence cases are unfortunately skyrocketing due to the current situation. This is an unfortunate consequence of spending more time with family when one is not interested in self-growth. If one is and the Torah certainly adjures us to do so then, aderaba, now is a time to work more on shalom bayis and being a good parent to our children assuring that the mesorah is warmly given over to the next generation.
As our sedarim this year are projected to be more parallel to the "שה לבית אבות" (one sheep per family with no others allowed in that group) of the first Passover in Egypt and not like the possibility of "chabura" (a pre-arranged group not restricted to the family exclusively) of subsequent Paschal offerings, let us reapply ourselves to becoming better people, better spouses, better parents so that when b'ezras Hashem soon when we can fully exit our homes, we can engage all aspects of avodas Hashem with even more fervor and perfection not just as individuals but as a holy nation. Sifrei chassidus compare sin to a spring; when the person is ready for teshuva, he is ready to fly even higher. Hopefully, we will be able to utilize this trying, but potentially elevating, time to emerge even better when Hashem has mercy on the world and brings salvation.
[1] This seems to be in contrast to the well-known analogy of the Chafetz Chaim who, when exhorting all to redouble efforts to bring people back to Judaism dismissing the claim that one doesn't know enough Torah or is not worthy for the task, stated, "a fire can be put out with dirty water also!" But there is no contradiction; each idea must be applied in the right time and place.