When sages predict an “end-date” for the redemption, this means that it is an opportune time for the redemption to come. The Zohar writes that in each generation there is a specific moment that is especially ripe for redemption. If the generation seizes the moment and prepares appropriately, the redemption may well come then. If not, however, the opportunity passes.

Additionally, even if the redemption did not come in actuality, each of these “end-dates” is associated with a significant event that marked our progress towards redemption. For example, at the end of year 5608 (1848), which was considered to be an “end-date,” the Tzemach Tzedek (third Rebbe of Chabad) was asked why the redemption did not come that year. He answered that in that year the Likutei Torah, a seminal work of Chassidic philosophy, was published.

The Rebbe of Komarna offered an interesting interpretation. When a Tzadik suggests an end-date, he is setting the time for the completion of his personal efforts to bring the redemption. He is hoping that through his efforts, he will bring the redemption for all of Israel.

The Alter Rebbe, founder of Chabad Chassidism, explains that Tzadikim view matters from a heavenly perspective. “Up there,” the light of redemption is in fact revealed on the end-dates predicted by the Tzadik. However, when that light is drawn down to this world, various obstacles can be thrown up to prevent the redemption from actually reaching the physical world. This applies only to end-dates that were not predicted by a prophet. However, if a prophet predicts an end-date, it will definitely be fulfilled.

(Zohar Chadash, Tikunim, 95:2. Sefer Hasichot “Torat Shalom”, p. 237. Heichal Habracha, Parshat Bereishit, p. 51. Migdal Oz, p. 508. Torat Menachem 5751, vol. 4, p. 202.)