I don't think I spent enough time writing this properly but I like this devar Torah anyway, enjoy it if you so desire.
The last aliyah of Parashat Titzaveh speaks about the commandment to construct the Mizbei’ach HaKetoret, the mizbei’ach upon which the sacred incense was offered inside the Mikdash. The Rishonim point out that this part of the parshah seems out of place, Parashat Terumah being a more fitting location alongside the other klei Mishkan. Why is it that the Torah listed the instructions to build the keilim (the Aron, Shulchan, Menorah…), then seemingly interposed a parashah about the Bikdei Kehunah, and then afterwards reverted back to speaking about the keilim with the Mizbei’ach HaKetoret? The Meshech Chachmah resolves this question of the Rishonim based on the Gemara in Zevachim 59a which says that if the Mizbei’ach HaKetoret were to be in some place other than its fixed spot in the Mikdash, the avodah of the ketoret would still be performed upon it. The structure of the mizbei’ach is not an essential component of the ketoret process in and of itself to extent that its displacement from its regular makom kavua disrupts the ability to perform the avodah. Rather, it is apparently only a means to offer the incense. Therefore it was written separately in the Torah from the other keilim. By the other keilim, they themselves are integral in the performance of the avodah associated with are necessary for the Hashra’at HaShechinah as well.
Rav Gedalyah Schorr offers a different explanation to the separate placement of Mizbei’ach HaKetoret. From the arrangement of the pesukim it seems that the main Hashra’at HaShechinah was already upon the Mishkan with the completion of the keilim listed in Parshat Terumah. Before the portion dealing with the Mizbei’ach HaKetoret, the Hashem says:
”וְשָׁכַנְתִּי בְּתוֹךְ בְּנֵי יִשְׂרָאֵל וְהָיִיתִי לָהֶם לֵאלֹקִים. וְיָדְעוּ כִּי אֲנִי ה' אֱלֹקֵיהֶם אֲשֶׁר הוֹצֵאתִי אֹתָם מֵאֶרֶץ מִצְרַיִם לְשָׁכְנִי בְתוֹכָם אֲנִי ה' אֱלֹקֵיהֶם. “ This would appear indicative that all of the preceding mitzvot were prerequisites to this point of Hashra’at HaShechinah and that once they were complete the hashra’ah took effect, even before the Torah mentions the Mizbei’ach HaKetoret. The division shows us some sort of special quality unto itself. This mizbei’ach created a unity between Hashem and Bnei Yisrael in some way unique from the rest of the keilim.
Chazal say in the Gemara in Shabbat 89a that when Moshe Rabbeinu went up to Shamayim, even the Malach HaMavet gave something to him, because when there was a plague going through Bnei Yisrael, Moseh told Aharon to bring ketoret, which caused the plague to stop. If the Malach HaMavet hadn’t told him about the power of the ketoret, how would Moshe have known? But how is it that that Moshe learned this from the Malacha HaMavet? Of Moshe it is said בכל ביתי נאמן הוא, how could he not know such a thing and only be able to receive it from the Malach HaMavet?
Rav Tzadok HaKohen M’Lublin explains that at the beginning of Creation, all of the Beri’ah gave something in contribution to the creation of Adam HaRishon, as the Torah says, נעשה אדם וכו' “Let us make man…” So Man basically contained some portion of everything in the Beri’ah. The purpose of this was so that Man should have the power to maintain dominion over all the land. However, the Satan did not give any of his chelek in Creation to Man, for if Adam HaRishon had possessed such a thing, he would immediately have turned this chelek rah into good and Man would rule over bad (i.e. the Yetzer HaRah, Malacha Hamavet, etc.). So in order to maintain free will this was not allowed to happen until the coming of the Mashiach when Hashem will obliterate everything evil. At Har Sinai, when Bnei Yisrael were at a level like that of Le’atid Lavo, they had freedom from the Malach HaMavet and Yetzer HaRah, so at that point in time the Malacha HaMavet gave his chelek in the Beri’ah to Moshe – the ketoret. The ketoret gave Moshe the strength to overpower evil and convert it to good; that is its yesod in being the contribution of the Malach HaMavet from the Beri’ah.
The unique unification quality of the ketoret was its ability to bind to the evil and change that evil to good. This quality is specifically connected to Aharon, of whom Chazal said was אוהב את הבריות ומקרבן לתורה, he loved everyone and brought them closer to Torah. Aharon elevated Bnei Yisrael and connected them to the kedushah of Torah. Even those who were distanced from the Torah Aharon reconnected to their roots.
We find by Moshe Rabbeinu the Torah says ויעמד העם על משה מן הבקר עד הערב. Chazal pointed out that this is obviously not possible if taken literally, to say that people were coming to Moshe the entire day. Rather it comes to teach that one who judges truthfully is considered a partner with Hashem in the Ma’aseh Bereishit. Here in Parashat Titzaveh, by the Menorah, the Torah says יערוך אותו אהרן ובניו מערב עד בקר וכו', because there was a tikkun in of Ma’aseh Bereishit here by Aharon and the Menorah as well. However, there is difference between Moshe and Aharon here. By Moshe the Torah says boker (morning, that which is light and holier) then erev (evening, that which is darker and less holy), because his avodah was to bring the Shechinah down to the world. By Aharon the opposite is true. His avodah was to elevate the lowliness of this world to the loftiness of the Upper World. This is the avodah of the Kehunah. This is why the parashah of the ketoret is so relevant to rest of Parashat Titzaveh; the parasha speaks about the Kedushat HaKehuna of Aharon, and the Mizbei’ach HaKetoret and the special unity it creates between Hashem and Bnei Yisrael and directly connected to (the idea of) Aharon HaKohen. Aharon connected the lowly to the lofty, and this is the avodah of any person to make himself worthy of Hashra’at HaShechinah, to elevate the mundane and transform it into that which is kadosh.