Shabbat is a repository of blessing and holiness, as it is stated: “And God blessed the seventh day and hallowed it, because on it God ceased from all the work of creation that He had done” (Bereishit 2:3). Similarly we read: “For in six days the Lord made heaven and earth and sea, and all that is in them, and He rested on the seventh day. Therefore the Lord blessed Shabbat day and hallowed it” (Shemot 20:11).
The word “kadosh” (holy) applies to the absolute, to that which is beyond time and place. “Kadosh” means separate and transcendent, for anything that belongs to the realm of the absolute is separate and distinct from all the finite things in the world. The word “blessing” (berakha) indicates increase and growth. The greater kedusha an item has, the greater source of blessing it can be. The holiest of all is God, the world’s creator, Who is, was, and will be. His light and power are infinite, and He is the source of blessing for all creatures. For this reason, He is called “the Holy One, blessed be He” (Ha-Kadosh Barukh Hu), for He is holy (transcendent) and blessed (bestows blessing).
God sanctified Shabbat and blessed it. He sanctified it by distinguishing it from other days, for on it the inner essence of the world is revealed. He blessed it, in that He bestows blessing on all the other days and on all worlds through it. Thus Zohar states: “The six weekdays all draw blessing from the seventh day” (II, 63b). It further states: “All the blessings from above and below depend on the seventh day, because all the supernal six days draw blessing from it” (ibid. 88a).
By God’s cessation of all work on the seventh day, it became the most sanctified and essential of all the days; through it God bestows blessing on the six days and on the world as a whole. So too the Jews, by ceasing all work on the seventh day and connecting to the holy source of blessing, understand the great value of every different type of work done in order to build up the world, and thus they draw down blessing upon themselves. This is as the Sages state: “The verse ‘The blessing of the Lord will enrich’ (Mishlei 10:22) refers to the Shabbat blessing” (y. Berakhot 2:7). They also state that by honoring Shabbat one merits wealth, because Shabbat is the source of blessing (Shabbat 119a).