A train’s engine is symbolic of the Jew’s G‑dly soul, to which we refer in our morning prayers: “The soul that You have placed in me is pure. As long as my soul is within me, I offer thanks before You….” This spiritual engine motivates the attached railway cars: the animal soul and the body. In more general terms, the engine is the mind and intellect, since the mind rules over the heart.

However, this Divine service cannot be chaotic and destructive. The Baal Shem Tov interpreted the verse, “You shall surely assist him” (Shmos 23:5) to mean that we must serve G‑d together with our bodies, rather than breaking the body with fasts and suffering. By serving G‑d physically, we forestall the need for any “severing of the connection and derailment of the cars.” Every day the good within the person progressively overcomes the evil — “little by little will I banish him from before you” — through the fulfillment of Torah and mitzvos in general, and Chassidus in particular. Regarding this mission, we are told that “it is not in heaven… for it is very close to you,” as explained by the Alter Rebbe in the title page of his book the Tanya, and as detailed in the text itself.

Since Torah is eternal, these words are relevant for every Jew, in every place and time.

Igros Kodesh, Vol. 13, p. 295