There is a quality to the mitzvah of dwelling in a Sukkah that is not found in most other mitzvos, in that the physical objects with which the mitzvah is performed — the schach (the Sukkah covering) as well as the walls — become holy.1 In other words, not only are the schach (and Rabbinically, the walls as well) used for the purpose of a mitzvah, but they themselves become sacred during the festival of Sukkos.

With regard to the mitzvah of the “Four Kinds,” we find that there is a more striking relationship with the physical objects with which the mitzvah is performed than is to be found regarding other mitzvos.

The physical objects with which all the various mitzvos are performed are more suited than other matter to being receptacles for G‑dliness. Thus, for example, the fact that wool is to be used for the commandment of tzitzis demonstrates that wool is intrinsically loftier than those other objects with which the mitzvah cannot be performed.2

The physical objects involved in the “Four Kinds,” however, not only possess this innate capacity to be used for a mitzvah , but clearly demonstrate this capacity.

Our Sages explain3 that the esrog , lulav , haddasim and aravos were specifically included in the “Four Kinds” because they each reflect unity. The branches of the lulav are all attached; the hadas has three leaves growing out of the same stem; aravos grow together in clusters.

And surely this quality applies to the esrog, which is found on the tree for an entire year — thereby uniting the climates of Spring, Summer, Winter and Fall.

Most other worldly objects exist as separate entities unto themselves. The fact, then, that these “four kinds” share a connection to unity points to the fact that within them is to be found a lessening of corporeality — a byproduct of their abnegation to holiness and G‑dliness.

Herein lies both the similarity and the disparity between the mitzvos of Sukkah and the “Four Kinds”: Both mitzvos are alike in that they — more than other mitzvos — reveal the innate capacity of physical objects to be used in the performance of a mitzvah.

The difference, however, lies in the fact that the sanctity inherent within the Sukkah is directly related to the performance of the mitzvah , while the relationship of the “Four Kinds” to its commandment is to be seen in the inherent nature of these plants, which makes them uniquely suited for the performance of the mitzvah.

There is yet another similarity and difference regarding these two mitzvos : A Sukkah envelopes an entire person (indeed, many people), thus pointing to a degree of sanctity that transcends differences.

The “Four Kinds” also reflect unity; not merely by their very nature, as explained above, but also by the fact that they all join to bring about the actualization of one mitzvah.

But here too, a difference exists between these two mitzvos: With regard to Sukkah there is no disparity even at the outset, while the “Four Kinds” are indeed separate to begin with, albeit uniting for the sake of the mitzvah.

Thus, the unity of the “four kinds” — a unity such that even after the kinds unite they remain distinct from each other — emphasizes how the world itself, whose very nature is divergence, becomes united with G‑dliness.

The transcendent unity of the Sukkah , however, points to a level of G‑dliness at which divergence and separation simply do not exist.

Based on Likkutei Sichos, Vol. XIX, pp. 356-359