There is a positive commandment to desist from any work involving the ground and the trees in the seventh year. There are three general mitzvot concerning this year:
1. Shevitat ha'aretz – allowing the land to rest completely in the seventh year; refraining from working the ground, tending to the trees or any related activities.
2. Shemittat hapeirot – declaring all produce of the fields and trees ownerless during this year, treating the produce with the appropriate laws of sanctity, and removing from one's home any produce that is no longer available in the fields, making it available to everyone alike.
3. Shemittat kesafim – waiving any debts owed to him at the end of the seventh year.
Calculating the seventh years is not reckoned from the creation of the world, rather they began counting the cycle fourteen years after Bnei Yisrael entered Eretz Yisrael, from the time they were settled in the Land which is when the obligation to observe Shemittah began. It follows that the first Shemittah they observed was twenty-one years after they entered the Land.
The mitzvah of Shemittah applies only in Eretz Yisrael as it says, "When you come into the Land that I give you, the Land shall observe a Shabbat rest for Hashem." Therefore, the laws of Shemittah regarding money do apply in chutz la'aretz as well, while laws regarding the land and its produce are not observed even as a rabbinical decree.
... The Sabbatical Year ...
