This week we read Parshios Achrei and Kedoshim. In Achrei, which means afterwards, Hashem instructs Moshe Rabbenu to tell Aharon to be careful to enter the Kodesh Kedoshim only on Yom Kippur after he makes special preparations. Aharon receives these instructions after his sons have died because they came too close to Hashem (as explained in Parshas Shemini). What practical lesson do we learn from this?
The Rebbe explains that the sin of the sons of Aharon was, according to the Ohr HaChaim, that they had such a desire to become one with Hashem that their neshamos could not remain within their bodies (a "desire without a return"). A person has to realize that however close and high he comes to Hashem, there must remain the purpose to come back into this world and use that experience to serve Hashem even better.
The Rebbe continues that a person may feel that he has reached such high levels, united with Hashem, that he doesn't feel after this elevated experience that there is more to do. Even when one comes to such a high level, there is Achrei - afterwards. A person should not be so satisfied that he or she says, “I have reached the pinnacle of service to Hashem!” There always must be the Achrei - afterward. This is what we find in Tanya, chapter 47, where the Alter Rebbe states that every generation and every day a person has to feel that today he is leaving Mitzrayim. This does not only mean leaving the evils of Mitzrayim, but also leaving one's limitations and boundaries, the boundaries of kedusha.
We are limited; as much as we serve Hashem there is always room to grow. Every day we have to exceed our limits and go beyond. No matter how good yesterday was, today we have to do better. This is the concept of Sefiras HaOmer. Every day that we count, we have to go higher. Every day there is something more to do than yesterday, and tomorrow has to be better than today.
With this idea, the Rebbe also explains a story of the Previous Rebbe. The Rebbe Rayatz came to his father, the Rebbe Rashab on the day after Yom Kippur and inquired, "What do we have to do now?" The Rebbe Rashab responded, “Now we have to begin to do teshuva.” How could this be? There was just an Elul, a Rosh Hashanah, a Yom Kippur! But the concept of teshuva is not only for sins, it also means to unite with Hashem. One reaches such a high level on Yom Kippur, but the next day still requires the avoda of Achrei – after – one can reunite with Hashem at even a higher level.
This is also a deeper reason why at the beginning of the Parsha of Achrei it speaks about Yom Kippur, while at the end of the Parsha it speaks about proper relationships. How do these disparate ideas all fit in one Parsha? Moreover, on Yom Kippur, we read from the beginning of Parshas Achrei, which speaks about the avodah of Yom Kippur, in the morning during Shacharis, and we read from the end of the Parsha, which speaks about forbidden relationships, in the afternoon at Mincha. Who, while fasting on the holy day of Yom Kippur, at the holy time just before Neila, is thinking about whom one is not allowed to live with, and must be warned against certain relationships? Why at this time do we say to beware of these forbidden relationships? This is the answer of the Rebbe: If a person feels at the end of Yom Kippur that there is no day afterward in one's service of Hashem, that there is no Achrei, and he has nowhere to reach higher because he has reached “the top,” he is warned that he risks slipping and falling to such a level that he will need to learn precisely those things. The only way to protect oneself is to look higher and continue to improve, just “keep on truckin'!”
Based on Likutei Sichos, vol. 12 and other Sichos