Asarah BeTeves, the tenth day in the month of Teves, is a public fast. On this day “The king of Bavel surrounded (“samach) Jerusalem and laid siege to it.1 ” This event marked the beginning of the Jewish exile and was the root of all subsequent tragedies of exile.

The later events — the seventeenth of Tammuz when the walls of Jerusalem were breached; the ninth of Av when the Beis HaMikdash was destroyed; and the death of Gedaliah on the third of Tishrei (or on Rosh HaShanah,)2 — all resulted from the initial siege that began on Asarah BeTeves.

Since the destruction of the Second Beis HaMikdash and the subsequent exile is a continuation of the destruction of the First Beis HaMikdash,3 it follows that Asarah BeTeves is the root cause of all of exile.4

This also explains why,5 according to the Avudraham,6 the fast of Asarah BeTeves is marked by a halachic stringency that is greater than the stringency found on all other commemorative fasts. For when any of those fasts fall on Shabbos, they are postponed to the following day. If, however, Asarah BeTeves were to fall on Shabbos, we would be required to fast on that day.

The Torah states a principle that “G‑d precedes a malady with healing,”7 which is to say, that as the “Ultimate Healer,” G‑d’s manner of healing is such that he “precedes the malady with healing” — He enables the greatest degree of healing possible, by not having the malady occur in the first place. This manner of healing helps not only in the future and not only retroactively, but also that from the very outset the malady does not occur.

We thus understand that the same is true with regard to the “malady” of exile, that G‑d precedes the exile with a manner of preventive healing that would preclude the need for exile.

As mentioned earlier, exile began with “The king of Bavel surrounding (“samach) Jerusalem and laying siege to it.” G‑d had already indicated how His healing could prevent the “malady” altogether. How did He do so?

Our Sages say8 that “baseless hatred” of one’s fellow Jew is the reason for the severity and length of this present exile. It follows that the means of “healing” and the method of “recovery” (redemption and liberation) from the ailment of exile is to engage in the very antithesis of “baseless hatred” — “baseless love” of one’s fellow Jew. (In its most perfect state, this refers to achieving absolute unity among the entire Jewish people.)

We must therefore say that even before the “malady” of exile began, within the siege itself (“the king of Bavel surrounded [“samach”] Jerusalem”) G‑d granted the capacity for peace and unity among the Jewish people. This would have prevented and “healed” the malady of exile in such a manner that it would not have occurred in the first place.

Where do we find the condition of peace and unity within a state of siege?

The effect of a siege is — as the verse states — that “none can leave or enter,”9 i.e., no individual living in the besieged city can leave it and all the inhabitants of that city are forced to remain together. Additionally, no “stranger,” no individual who is not an inhabitant, can possibly enter the city.

Now in this instance we are speaking of the siege of the city of Jerusalem, the “city that is united together,”10 which our Sages understood to mean that “Jerusalem unites and links all Jews.” 11

The siege of Jerusalem thus caused the inhabitants of this sacred and unifying city to be thrown together to an even greater extent than they would have been had the city not been under siege. Consequently, the “affliction” of the siege itself should have brought about the healing — it should have resulted in Jews achieving a greater unity and love for one another: “baseless love.”

Moreover, it was clear here how G‑d “precedes the malady with healing,” for while the negative effects of the siege — lack of food, water, etc. — were not felt until much later, the positive and unifying effect of the siege was immediately felt.

Hence the unusual Hebrew term used here for “siege” — samach.12 In Hebrew, the term samach usually has the positive meaning of “support.” Why is it used here to describe a siege that served as the precursor to all of exile?

For at its source, this siege, enhancing as it did the ability of the Jewish people to achieve a greater degree of unity and “baseless love,” was surely a positive and “supportive” manifestation. It was only after the Jews did not choose wisely and “baseless love” did not result that the siege was transformed into a negative event.

Asarah BeTeves thus first and foremost reminds the Jew that the manner in which to nullify any and all “afflictions” and “maladies” is through “baseless love” of one’s fellow Jew, and as expressed in its most complete state, absolute unity among the Jewish people.

This, in turn, will lead to the nullification of these sorrowful fast days;13 so that they will be transformed — with Mashiachs arrival — into “a Yom Tov and days of joy and gladness.”14

Based on Likkutei Sichos, Vol. XXV, pp. 267-269.