At the time of Matan Torah, Hakadosh Baruch Hu called down to Klal Yisroel and he said, “My child! I have a great present to give to you, but I will only give it to you if you keep my Torah and its Mitzvos.” Klal Yisroel responded curiously, “Ribbono Shel Olam! What conditional present do you have for us that we can only receive if we keep your Torah?! Hashem answered, “Olam Haba [The World to Come]”. Klal Yisroel anxiously responded, “But how are we supposed to aspire for something that we cannot comprehend? Please, show us an example.” Accepting his nations proposal Hashem answers, “This is Shabbos, for it is 1/60th of Olam Haba, for Olam Haba is entirely Shabbos." - Osios DiR'Akiva
People get discouraged by the concept of Olam Haba, they feel that it is too distant from reality and that it is an unattainable goal. The truth of the matter is, that if we picture attaining Olam Haba as being similar to the way that one attains Shabbos (1/60th of Olam Haba), then it makes Olam Haba all that much more feasible.
Shabbos is the paradigm of completion. After six days of creation the entire world was seemingly lacking nothing. During these days even the angels were created (See Ramban). One Shabbos came however, the world realized that something in fact had been missing, Menucha (rest).
Breishis Rabba brings a parallel mashal to the story of creation. There was once a king who made a complete and extravagant wedding. He even made a pristine canopy that was perfect for the ceremony and the later wedding festivities. Nevertheless, something was still missing, the Kala (bride), who was eventually subject to walk under it. The same was the story of the world during creation. It seemed that after six days the world was complete, lacking nothing! Then Shabbos came, and they came to a stunning realization; Shabbos was what the world needed to be truly complete. This day of Sabbath, is the crux of an existential but yet spiritual existence, only through it can the Shechina dwell in this world in order to weekly complete the creation of the world.*
* Michtav Mi'Eliyahu, Beginning of Krach Beis