It is brought in the Asarah Maamarot: “Eileh Mas’ey (These are the journeys) of the Israelites” (Numbers 33:1) —because they sinned with “Eileh (This is) your god, Israel” (Exodus 32:4), as a result the Israelites journeyed.

We see, then, that all a person’s journeys are because of a blemish in faith—i.e., an aspect of idolatry. For if he had believed with a perfect faith that God could provide him with all his needs at home, he would certainly not have set out on any journey. Consequently, the journey [indicates] a blemish in faith—i.e., an aspect of idolatry.

This is what is written of idolatry: “Tell him, ‘Get out!’” (Isaiah 30:22). It is an aspect of journeying and wandering.

And by virtue of his wandering, he rectifies the wandering he caused Above, as it were. As it is written (Isaiah 28:20), “and the cover is too narrow for curling up.”

Also as a result of idolatry, rain does not fall, as is written (Deuteronomy 11:16,17), “[Take care not]… to serve others gods… for there will be no rain [and the ground will not yield its produce].” And when there is no rain, there is no satiation. And when there is no satiation, there is no peace, as Rashi explains the verse (Psalms 72:3), “Let mountains bear peace for the nation.” For when peace is lacking, then people do not help one another, so that each has to journey and wander from place to place to earn his livelihood.

Another cause of exile is the interruption of Torah study, as is written (Isaiah 5:13), “My nation has been exiled, for they lack knowledge.” And idolatry brings drought, and when there is no flour, there is no Torah (Avot 3:17).