Free translation from a talk of the Rebbe, Shabbat Parshat Bamidbar, 5746 (1986) (excerpt)

Having previously designated this Shabbos afternoon as a time for gatherings of unity and love [see essay: Unity & Love] now that we are gathered, we can discern deeper meaning and greater significance in this universal expression of Ahavas Yisrael and Jewish Unity.

We will find this unity enhanced by various aspects, such as the fact that this year is a leap year which unifies the solar year and lunar year.

The solar year is usually about eleven days longer than the regular lunar year, therefore when the gap reaches approximately 30 days, a leap year is pronounced and the 13th month is added to the year. Following this system, it sometimes occurs that the leap year will have more days than necessary to make up the accrued deficit of the moon years to that point, and will be longer than the usual sun year. Nevertheless, in such a case the extra days are added in advance of the deficit.

The leap year thus provides a unification of the “great luminary” with the “small luminary” in a manner that equalizes both of them.

In our Divine service we may also find an example of this unification of great and small.

Among the Jewish people there are also divisions between great and small which might cause jealousy or competition. Sometimes there are situations where this jealousy could bring a positive outcome. As the Talmud states:

The jealousy of scribes (scholars) increases wisdom. (B. Basra 22a)

The lesser also contributes to the greater one, as in the case of a student and teacher. The true teacher is really in a loftier league than his student, yet the teacher may also benefit from the student more than from his colleague and teacher (cf. Taanis 7a).

The student, on the other hand, must aspire to raise his talents and intellect to reach the level of his teacher and actually be like the teacher, thus forging a unity between giver and receiver. Then there will be no need for one to absorb and nullify the other, rather they both combine and fuse together as one.

There is another aspect of unity as a result of the proximity of Shabbos and Rosh Chodesh. Shabbos leads directly into Rosh Chodesh with no interruption, and under certain conditions it would be permissible to pray the evening service before sunset while it is still Shabbos, and at the same time you would recite the portion of Ya’aleh Veyavo, for Rosh Chodesh, while it is still Shabbos. In that case you have united Shabbos with Rosh Chodesh.

Yet another aspect of unity on this Shabbos is the setting of Rosh Chodesh on Sunday.

Chassidus explains that every Sunday is symbolic of the first day of creation, which was called “one day” (not the “first day”), for G‑d was one and alone in His world; even the angels were not created till the second day of creation. So that on the first day G‑d was truly alone and one. We, too, are referred to as “one nation in the land,” and this gives us the power to reveal G‑d’s uniqueness in the land, and this also brings to unity among the Jewish people as well as Ahavas Yisrael.

In today’s Chumash portion we find reference to this unity and our discussion and involvement in the subject will increase the Ahavas Yisrael and Jewish Unity.

Practically speaking, may our discussion bring to Jewish Unity and to Ahavas Yisrael — “Love your neighbor as yourself”; as two limbs of the same body.

Coming before Shavuos this Shabbos is associated with the verse “Israel camped opposite the mountain,” on the first day of Sivan. Why? Because when they came to the mountain where the Torah would be given they camped in perfect unity.

May the increase in Ahavas Yisrael nullify the causes of the galus and when the cause disappears the galus will dissipate and immediately we will merit the true and complete redemption through our righteous Mashiach quickly and speedily in our days.