“The Jewish Sabbath is unique.
Indeed, a comparison with the Christian and Muslim imitations of it—not to mention the modern secular ‘weekend’—only underlines this uniqueness.
Shabbat is not simply a day when one refrains from work, nor is it merely the day when it is customary to attend public prayer.
It is a day when one enters a completely different sphere.
The rabbinic sayings comparing Shabbat to the world to come are more than mere figures of speech.
Basically, Shabbat means putting aside creative activity in order to concern oneself completely with personal reflection and matters of the spirit, free of struggle and tension.
The key element in Shabbat observance is a kind of passivity: refraining from ‘work.’
Yet, over a period of three thousand years, the Jewish people have developed a tradition that transforms what might otherwise be a day of mere inactivity into one of joy and inner peace, ‘a day of rest and holiness,’ in the words of the liturgy.”
–Rabbi Adin Steinsaltz
From Teshuvah by Rabbi Adin Steinsaltz