From a letter of the Lubavitcher Rebbe, 1981
...It is appropriate that we speak of Yud-Tes Kislev, the liberation of the Alter Rebbe from imprisonment on the 19th of Kislev. As with all things connected with Judaism, talking about Yud-Tes Kislev must be such that it lends vitality to and permeates all one’s limbs and faculties.
Since the words spoken are the words of G-d in His Torah, true and everlasting, they lead to deeds, both that of the speaker and listeners. As the Alter Rebbe writes in Tanya, that “the thing is very near to you in your mouth and in your heart that you may do it.” First comes speech (your mouth) which stimulates the feelings in “your heart,” and through this they come to fruition in deed (“that you may do it”).
The central theme of Yud-Tes Kislev is the liberation of the Alter Rebbe from imprisonment because of his work in spreading Judaism and Chassidus. Knowing that he was endangering his life, he still threw himself into this work, disregarding all obstacles. For although Jewish law regards “the law of the country as law,” this only applies when the government’s laws are not at variance with the fulfillment of Torah and mitzvos. The previous Rebbe, in the name of his father the Rebbe Rashab, said that the soul (of a Jew) can never be in exile; hence no person can dictate to a Jew how to behave in matters of Judaism.
The Alter Rebbe was imprisoned because of his work in spreading both the exoteric and the esoteric parts of Torah. His imprisonment for 53 days, eventually brought about greater good than before – greater dissemination of Chassidus. This can be compared to the concept of “the superiority of light (greater dissemination of Chassidus) that comes from prior darkness (the imprisonment).”
Hence, when we remember and meditate on the events of Yud-Tes Kislev, it brings us to greater efforts in spreading Judaism and Torah. This should be in a manner above and beyond normal limits, disregarding all obstacles, even to the extent of literal self-sacrifice. In such a manner our efforts will be with enthusiasm and vitality, with joy and a good heart.
Just as the liberation then caused greater dissemination of Torah and Judaism, so must it be today, in regard to each and every Jew, men, women, and children. In all those things to which the Alter Rebbe dedicated his life, all of us must know that “the thing is very near to you in your mouth and in your heart that you may do it.” Then we may be sure that “we will have the upper hand” – we will surely be successful in battling the exile.
This day is an auspicious one for making good resolutions in spreading Judaism and Torah. Just as the Alter Rebbe was completely exonerated and victorious, so too today in each person’s fight against his personal exile, and against the darkness of the general exile. Then will be fulfilled the Rambam’s Halachic statement that “Torah has promised that eventually Yisroel will repent... and immediately they will be redeemed,” in the true and complete redemption through our righteous Moshiach.
