This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
Most melodies are written to be sung whenever the occasion calls for singing. Daled Bavos was written to be sung almost never. Chabad-Lubavitch Hasidim reserve it for a short list of moments the community treats as carrying unusual weight: 19 Kislev, the date marking the release from imperial imprisonment of the man who composed it, the High Holidays, and weddings. Outside those occasions the melody largely stays silent, which is itself part of what the community understands the piece to be doing.
The composer was Rabbi Schneur Zalman of Liadi, the first Rebbe of Chabad-Lubavitch, who lived from 1745 to 1812. Tradition holds that he began shaping the tune while he himself was a student under his teacher, the Maggid of Mezritch, and continued refining it after he had become a Rebbe in his own right, though no source consulted for this entry pins the composition to a single settled year. What is agreed on is its shape: four distinct sections, called bavos, or gates, one after another, without a single word of text anywhere in the piece.
The four gates are said to correspond to four spiritual worlds named in Hasidic and kabbalistic thought, Atzilus, Beriah, Yetzirah and Asiyah, with each section of the melody meant to carry the singer and the listener up through the next world in the sequence. Carrying no lyrics at all is not treated as an absence. Within Chabad thought a wordless niggun is its own form of speech, understood as more direct than language rather than less expressive than it, which is part of why a melody with nothing to say in words is treated as saying something all the same.