Our parashah tells about the mitzvah of Shmita: "For six years you shall plant your fields, gather your vineyards, and harvest your produce, but the seventh year is Shabbat... plow the land.".
If we have already been given the mitzvah of Shabbat, a special day of rest, why does the Torah give us an additional mitzvah of rest: is one day a week not enough?
Shabbat and Shmita seem similar. Both mean to stop working and rest from our ordinary work.
When a Jew stops working on Shabbat, he spends his time praying, studying, singing, eating, and thinking about why HaShem sent his neshamá - soul - to this world. During the week we are very busy. Snabat does not give extra time to think about holy things.
But when Shabbat is over, we return to our weekly activities. Then HaShem gives us a whole year to spend more time studying Torah and reflecting on what HaShem wants us to do. That year strengthens us.
It works in two ways. On one hand, the six days of the week are a preparation for Shabbat, and the six years of ordinary work are a preparation for the Shmita year. On the other hand, Shabbat and Shmita prepare us for the days and years that follow, and show us how we can make this world a better place.
Extracted from Please tell me what the Rebbe says.