more on the importance of physical mitzvos

 Briefly, the explanation of this is as follows: Mitzvahs can be performed only with physical substance. For example: tsitsit [tallit fringes] are made of physical wool, the Four Species waved on Sukkot are physical plants, and a mezuzah is written on physical parchment. Through doing mitzvahs with physical objects we can transcend the separateness of the physical that we perceive with our senses and realize our true nothingness in relation to G‑d: that the created existence is nothing and the Creator is the true existence. Then G‑dliness can be revealed through us and to us.

When we meditate upon the verse "I, G‑d have not changed" (Malachi 3:6), we understand that the apparent change (during Creation from spiritual into physical through the concealment of the spiritual) is only from our perspective; from G‑d's perspective, however, there is no darkness or concealment of His Infinite Light.

From the teachings of Rabbi Sholom DovBer Schneersohn of Lubavitch; adapted by Moshe Kravitz