The round of weekdays and Sabbaths is without end.
On the one hand, the weekdays prepare the Sabbath, correcting and providing additional plenty to the world, making it possible to bring things to a conclusion and to raise them to a suitably higher level.
On the other hand, the Sabbath is the source of plenty for all the days of the week that follow it.
The surrender of oneself on the Sabbath is not simply a matter of no activity but of opening oneself to the influence of the higher worlds and thereby receiving the strength for all the days of the week that follow.
–Rabbi Adin Steinsaltz