The second half of Sefer Shemot presents us with a detailed account of the construction of the Mishkan, from G-d’s initial command to build it all the way through its actual assembly. Sefer Vayikra continues the Mishkan theme by describing the different types of korbanot (sacrifices). At this point, the seven-day inauguration festival begins, and Hashem’s presence visibly returns to the midst of the people. At this moment of triumph, Nadav and Avihu offer some sort of unwelcome offering, and they are immediately punished by Hashem with death.

On the heels of this tragedy, the Torah continues with what appears to be an entirely unconnected set of new laws, first listing which animals are kosher (in last week’s parshah) and then (in this week’s parshah) listing the ways a person can become impure and how to cleanse oneself of impurity. Only in perek 16, four perakim later, does the Torah return to “after the death of the two sons of Aaron, when they drew near before the L-rd, and died.” Why does the Torah interrupt what should have been a smooth flow from Parshat Shemini directly to Parshat Achrei Mot, placing Parshiyyot Tazria and Metzora right in the middle?

Throughout the entire building project of the Mishkan, one simple phrase appears again and again: “Ka-’asher tzivah Hashem et Moshe,” “As Hashem commanded Moshe.” Following every Mishkan-related instruction, this pasuk reappears. Why? According to Rashi, the Mishkan was built as atonement for the Golden Calf. Regardless of what the actual sin was, one thing is certain: This was not a commandment from G-d, but an idea devised by Am Yisrael. G-d then creates a framework for us to connect and relate to Him. By following the framework that G-d has created, Am Yisrael can achieve atonement; hence the constant reminders, “This is the thing which Hashem commanded.”

The story of Nadav and Avihu is a perfect example of lack of compliance with “Ka-’asher tzivah Hashem et Moshe.” Like the story of Chet HaEgel, the sin of Nadav and Avihu is not so clear; but whether they were punished for being drunk, for not getting married, or perhaps were showing disrespect to Moshe, as the Midrash suggests, the Torah does clearly tells us, “Nadav and Avihu each took their fire-pan, put in it fire and added incense, and they brought an alien fire to G-d, which He had not commanded them,” “Asher lo tzivah.” This offering was brought on their own, without any sort of instruction from G-d

The Torah then “takes a break” from this story to explain the circumstances under which a person is not allowed to enter the Mishkan. What are these laws doing here? This section of laws ends with the following key pasuk: “Ve-hizartem et Bnei Yisrael mi-tum’atam, ve-lo yamutu b’tumatam b’tamaam et mishkani asher b’tocham”, “You shall put Bnei Yisrael on guard against their impurities, lest they die through their tumah by defiling My Mishkan which is among them” (Vayikra 15:31). The Torah connects the laws of impurity to the Mishkan by warning all of us that when we are impure, it is forbidden to enter the Mishkan. Being impure is not in itself a sin. It is problematic only if an impure person enters the Mishkan.

G-d removed His Shechinah from us after we were “Asher lo tzivah” and built the Egel HaZahav. G-d benevolently rebuilds His relationship with us through the building of the Mishkan, and can now return to our midst. Our closeness to G-d is dependent on our following His rules. When we break the rules, as Nadav and Avihu did with their improper entry into the Mishkan, than we are not capable of maintaining this relationship. Parshat Tazria explains the commandments of Tumah and Tahara which regulate who can and cannot enter the Mishkan. Only once we have fully internalized “the thing which the L-rd commanded” and have followed the guidelines as prescribed by G-d, are we ready for the ultimate relationship, of Parshat Acharei Mot, of the Kohen Gadol entering the Kodesh Ha-Kodashim.