There is a Midrash that says that there was a conversation between G-d and the Jewish people. Hashem told them that He is giving Israel an eternal gift. It is עולם הבא, the World to Come, if they agree to follow the Torah and its commandments.
The Jewish people asked if they could see a sample of what Olam Haba would be like. G-d answered that Shabbat observance gives one sixtieth of the pleasure experienced in the next world.
We see from this week’s Parsha that after creation, the Torah says that G-d completed all of His work on the seventh day. This is strange because the world was created in six days. The world was lacking only one thing; Menucha, or rest.
The secret of the delight of Shabbat is the ability to see all of every individual’s work completed at sunset on Friday evening. Everything is put on hold until Saturday night. When one is able to distance himself from the material, physical world for one day, he is able to experience this bliss. He demonstrates that he is a free man, and not imprisoned by the technological and mundane.
Instead, he allows himself to focus on his own spirituality, and he is able to achieve real rest. This is invigorating and gives added strength to face the issues of the coming week.
The realization that we must force ourselves to stop what we are doing for one day, is extremely beneficial for our physical and spiritual well being. It is so true that this Menucha was the one missing part of creation. And when observed properly, Shabbat is truly a taste of the World to Come.