The sicha of Vayishlach 5752 contains several threads, each of considerable significance.
Firstly, the Rebbe explains the concept of the diminution of the moon — that the full moon on the 15th of the lunar month, when the moon fully receives and reflects the light of the sun, is followed by a decrease in the light until it completely disappears from sight. However, this period of diminution of the light of the moon is really only as far as the revelation of the moon is concerned. But the fact that we continue to count the days up (16th, 17th, 18th, etc.) hints that in fact the moon is really reaching a higher level, coming closer to the sun (the mashpia) until it ultimately unifies with it and becomes a mashpia itself. “The complete perfection of the moon is when it becomes like the sun and no longer needs to receive the light of the sun.“
The unification of the sun and the moon, the mashpia and the mekabel, requires the moon to be completely nullified, resulting in “the essence being revealed” (etzem b’hisgalus). This is a metaphor for the relationship of the Jewish people to Hashem, that when Yisroel is completely nullified to Hashem they become unified and they themselves become like Him, both being equal “one crown for both of them”. All this takes place after the process of refinement (avodas habirurim) is completed.
This brings us to the next significant thread of this sicha, where the Rebbe states that the refinement of the sparks of Tohu (related to Esav in our parsha) has been completed, and “all the matters of avodah have been finished and completed, also as regards (and in) the world.” Although this appears in many of the sichos of Dvar Malchus, in our sicha of Vayishlach the Rebbe addresses the question: if everything has been done, what do we do now? The answer is found in the conduct of Yaakov towards Esav in our parsha. Returning from living with Lavan in Charan, Yaakov was ready for Moshiach and anticipated that Esav, too, was ready. Thus, what Yaakov did is what we are doing. The verses tell us how Yaakov sent excessive gifts to Esav, and bowed down 7 times. In Torah Ohr, the Alter Rebbe explains what this means spiritually, which the Rebbe summarizes as follows:
“Yaakov sent messengers before him to Esav his brother” — that Yaakov, whose source is from the world of Tikkun, sent messengers literally “before him“, to the level that is higher than him, to Esav his brother who has his source in the world of Tohu (since, due to his relationship to Yaakov, we are referring to Esav after he was refined and returned to his source, the transcendent level of Tohu). This was “in order to draw down the transcendent level of Tohu to him below in Tikkun, which is the aspect of internalized light, that the transcendent will shine forth internally and they will be unified together. This is also the meaning of the unification of the moon and the sun (Yaakov and Esav, inner light and transcendent light, memaleh kol almin and sovev kol almin), until the moon no longer receives from the sun (since the the refinement of the sparks of Tohu has already been finished and completed, which was the reason that the moon was originally diminished to be a receiver, as explained earlier in the sicha), but rather the light of the moon becomes like the light of the sun, that both are equal.
(Footnote 89): We learn out from the avodah of Yaakov after he thought that Esav was already refined, and even after the messengers returned and informed him that Esave was not yet refined — he did not get involved in “avodas habirurim” (to refine Esav), but rather he became involved in “the elevation of the ‘lower waters’ to draw down the ‘masculine waters’ of the transcendent level of Tohu‘ [in the original: hala’as ma”n lehamshich ma”d d’makif d’Tohu] via his offering. [More explanation is required, but time does not allow us to do so here and now. See Torah Ohr on this week’s parsha.]
The Rebbe continues and connects this with the refinement of the nation of France, in loshon kodesh “Tzorfas” which has the numerical value of 770, that this represents the completion of the process of refining the world. “From this it is understood that literally in our times we need only to open the eyes and to see the reality b’poel mamash.” (Footnote 112): “That is to say, not only this that the avodah of refinement has been completed and that we need to bring about a revelation of this in the world, but rather more than this, that there is [such a revelation] already revealed in actuality, and we need only to open the eyes, because already ‘you have been given…eyes to see.'”