Likutei Moharan 31:3/ליקוטי מוהר"ן ל״א:ג׳

13 . And know! faith is only lasting because of the concept of brit (the Covenant), as in (Psalms 89:29), “My covenant shall remain faithful to him.”

2And thus Covenant is associated with Shabbat, as is written (Exodus 31:16,17), “an eternal covenant, between Me and the children of Israel [that… on Shabbat He ceased working and He rested].” And this is (Jeremiah 33:25), “Were it not for My covenant with day and night, the ordinances of heaven and earth I would not have appointed.” For the ordinances of heaven and earth—i.e., the galgalim —are dependent upon the Covenant.