Likutei Moharan 57:4/ליקוטי מוהר"ן נ״ז:ד׳

14. By means of these lights, a person ascends and delights in the delight of Shabbat, in the aspect of “Then you can delight… I will let you ride the heights of the earth, and I will give you to enjoy the inheritance of your father Yaakov” (Isaiah 58:14). “The heights of the earth” are Avraham and Yitzchak, who are the hands, for they are the “arms of the world” (Deuteronomy 33:27). “I will give you to enjoy the inheritance of your father Yaakov”—this is the above mentioned vow. By means of the patriarchs and the above mentioned faith, he merits the delight of ShaBbaT.

2[Shabbat] is the aspect of Shin BaT. Shin is the aspect of the patriarchs. BaT is the aspect of faith, the aspect of “Avraham had a bat,” the aspect of “A faithful man has abundant blessings” (Proverbs 28:20) .