Likutei Moharan 31:4/ליקוטי מוהר"ן ל״א:ד׳

14. And know! the difficulties that a person encounters when travelling are caused by the celestial bands. For there is nothing below that does not have a corresponding star Above (Bereishit Rabbah 10:6). There are stars that cause certain grasses to grow in those places on which they shine; others that necessitate there be roads in the places on which they shine; others that necessitate there be a desert; and others that necessitate there be settlements in the places on which they shine. And in line with the way the stars shine on a place, such is the nature of that place.

2This is the meaning of, “The ways of Zion are in mourning, with none coming at the appointed time” (Lamentations 1:4). “Appointed time” corresponds to the celestial bands through which time is calculated.

3And this is, “The way of the wicked is as darkness” (Proverbs 4:19). The stars and constellations do not shine for them, and so they stumble. It all depends on the Covenant, as in, “Were it not for My covenant with day and night….”

4And this is the meaning of, All roads are considered dangerous (Jerusalem Talmud, Berakhot 4:4). This corresponds to, “Have I ever endangered you?” (Numbers 22:30). That is, travel requires guarding the brit. Because of this, a man is obligated to be with his wife before setting out on the way (Yevamot 62b) ; so that he should not be in the category of “all flesh had perverted its way” (Genesis 6:12). In other words, by guarding the brit he will not experience any distress on the road.