As the name suggests, Yud Tes Kislev is simply the 19th day of the Hebrew month of Kislev. It isn’t an ordinary day, though- instead, it carries special significance within the Chabad Chassidic world. It marks the release of the Alter Rebbe from prison. The Alter Rebbe (literally ”old Rebbe”; also known as the Baal HaTanya and Rabbi Schneur Zalman of Liadi) was imprisoned in Russia and charged with treason, due to his inherent connection with the Holy Land of Israel (then a part of the Ottoman Empire). He was imprisoned for fifty three days (coincidentially, the first section of his work, the Tanya, is made up of 53 chapters) before finally being released on Yud Tes Kislev. And thus, the day is a celebration of Divine mercy and illumination.
There are two ways in which we commemorate the day. The first is by ommiting Tachanun, the supplicatory prayer, just as we do on Shabbes. And the second way is to hold gatherings which infuse both joy and learning; both love for our Creator, and wonder for the world around us. These gatherings are known as farbengens. They mark the joyous nature of the day in a truly unique way- after all, Yud Tes Kislev is like Rosh Hashanah- it’s the new year for Chassidism!
This year, Yud Tes Kislev begins in the evening of Sunday 18th December, and ends in the evening of Monday 19th December. May you be signed and sealed for a good year in the study and ways of Chassidus!