From the Rebbe’s explanations:
– The 90th Chapter of Tehillim is concluded by the following verse:
“May the pleasantness of G‑d, our L‑rd, be upon us; establish for us the work of our hands; establish the work of our hands.”
Our sages interpret this as a prayer in connection with the construction of the Mishkan built in the desert. With this prayer, Moshe permanently established the dwelling of Shechinah (the Divine Presence) among the Jewish people. The ultimate expression of this indwelling will be in the Era of Redemption, with the construction of the Third Beis HaMikdash, which will be an eternal structure.
Remarkably, the literary structure of repetition is employed both at the beginning (“A prayer of Moshe, the man of G‑d”) and at the end of this Psalm (“establish for us the work of our hands; establish the work of our hands”). What is the intention of this repetition?
There are two qualities which are necessary to establishing G‑d’s indwelling within the Jewish people in a permanent manner:
a) One must have a power which is greater than the natural order that can infuse a revelation. of G‑dliness into this world which is characterized by concealment. This involves changing the nature of the world as it were, making it into a vessel intended to receive G‑dliness, and indeed, to receive G‑dliness in a permanent manner.
b) This power must descend to the extent that it can enclothe itself within the world (for the entity which refines another entity must be on its level). Only in this way, will it be able to transform the world into a vessel that can receive G‑dliness in a permanent manner. Indeed, if the nature of the revelation is above what the recipient is able to accept, it will not be able to be internalized and the effect it produces may decrease as time passes.
These two qualities are alluded to in the repetition of the beginning and conclusion of the above psalm, because both these qualities were present within Moshe.
Moshe served as “an intermediary who connects,” binding the Jews to G‑d.
The two qualities that an intermediary must possess are reflected in the phrase “the man of G‑d.” Our Sages commented:
“His upper half resembled G‑d; his lower half was like a man.”
More particularly, however, it is the phrase “Moshe, the man of G‑d,” which brings out these two dimensions. The name for G‑d used in the above phrase is E-lohim (א-להים) which is numerically equivalent to the word hateva (הטבע), meaning “the nature”. The Name ‘E-lohim’ refers to the G‑dliness which brings the natural order into being.
Thus the phrase “The man of E-lohim” refers to a person who has been able to establish a oneness with this G‑dliness. It does, however, represent a limitation, for one unites only with the G‑dliness that invests itself within nature and not with the essential G‑dliness that transcends the natural order (in Kabbalah it is represented by the Name Havayah (י-ה-ו-ה).
However, the name ‘Moshe’ as such refers to this higher level.
The Torah states that he was given this name because “I drew him from the water.” In the chassidic teachings, “The water” refers to the name Havayah, the level of Mah, the G‑dliness which transcends creation. Moshe’s soul had its source in these high levels of G‑dliness and from these levels, it was drawn into this world. Furthermore, even as Moshe existed within this world, his soul was united with its source in the spiritual realms like fish who live in constant contact with their source of life.
Thus the phrase “Moshe, the man of G‑d,” represents the two qualities mentioned above: Moshe represents the connection with the levels of G‑dliness which transcend nature. Since this connection continued even as Moshe existed within this material world, he had the potential to reveal G‑dliness within the world and transform its nature in a permanent manner as explained above.
“The man of G‑d” emphasizes the other dimension, the connection with the world which allows G‑dliness to be drawn down within the world in an internalized manner, and thus allow for permanent change. This way the revelation of G‑dliness which is above nature can be drawn into the creation itself.
From the Rebbe’s talk on Shabbat Parshas Tzav, 8th Day of Nissan, 5751 (1991).