לקוטי שיחות חלק יח - מסעי-בין המצרים

The teaching in the Gemara, “Tziyon — no one seeks her; this implies that she requires seeking,” means only that there must be a remembrance of the Mikdash. However, through “Seek the peace of Yerushalayim” — studying the form of the Beis Hamikdash — one is involved in the building of the Beis Hamikdash itself.

In Parshas Masei, the passing of Aharon is related. On the one hand, the day of the passing of a tzaddik is a day of mourning. On the other hand, it is a time to be awakened by all of his deeds, until we bring about the idea that “just as his descendants are alive, so too he is alive.”

The same applies to the days of the Three Weeks. They are days of mourning, but through involvement in the form of the Beis Hamikdash, Hashem says, “I consider it as though you are involved in building it.”

The meaning of this is not merely “as though” in a symbolic sense. Rather, this is the fulfillment of the mitzvah, “They shall make Me a sanctuary, and I will dwell among them,” which is an eternal mitzvah. When the Jewish people are unable to build the actual structure in practice, the study of its laws and form becomes part of the definition of the mitzvah itself.

This explains why the Rambam brings the verse “Seek the peace of Yerushalayim” as an introduction to Sefer Avodah, even though the Gemara brings a different verse as the source for making a remembrance of the Mikdash: “Tziyon — no one seeks her; this implies that she requires seeking.”

The reason is that the Gemara’s teaching establishes only that there must be a remembrance of the Mikdash. But through “Seek the peace of Yerushalayim” — studying the form of the Beis Hamikdash — one is involved in the building of the Beis Hamikdash itself.

Just as with the Third Beis Hamikdash there is a part that will be built by man and a part that will descend from above, so too with the study of its laws: the learning itself comes from man, while Hashem’s statement, “I consider it as though,” is the part that comes from above.

From this we learn the importance of studying the form of the Beis Hamikdash, especially during the days of the Three Weeks.