The Baal Shem Tov writes in a letter (Reproduced in Keser Shem Tov [Kehos NY 1981 p3) that on Rosh HaShonoh of the year 5507 (1746) his soul ascended to the heavenly realms, where he was granted the privilege of entering the palace of Moshiach. He writes as follows: I asked the King Moshiach, “Master, when are you coming?” And he replied: “When your wellsprings will be disseminated outward.” (Mishlei 5:16 The metaphor of “wellsprings” signifies “teachings”.)
On this exchange the Rebbe Rayatz commented: “From this reply it is apparent that the teachings of the Baal Shem Tov - the revelation of the Divine Intellect which the Baal Shem Tov and his disciples and their disciples (our forefathers, the Rebbeim) bequeathed us - are very closely connected with the coming of Moshiach. ... Moshiach is an Ohr Atzmi, quintessential light itself, and the teachings of Chassidus are the vessel for this great light.” (Likkutei Dibburim Vol.2 p269/273/4).
