Rabbinical Interpretations
The rabbis of the Talmud and later times interpreted the Shmita laws in various ways to ease the burden they created for farmers and the agricultural industry. The Heter Mechirah (leniency of sale), developed for the Shmita year of 1888-1889, permitted Jewish farmers to sell their land to non-Jews so that they could continue to work the land as usual during Shmita. This temporary solution to the impoverishment of the Jewish settlement in those days was later adopted by the Chief Rabbinate of Israel as a permanent edict, generating ongoing controversy between Zionist and Hareidi leaders to this day. There is a major debate among halakhic authorities as to what is the nature of the obligation of the Sabbatical year nowadays. Some say it is still biblically binding, as it has always been. Others hold that it is rabbinically binding, since the Shmita only biblically applies when the Jubilee year is in effect, but the Sages of the Talmud legislated the observance of the Shmita anyway as a reminder of the biblical statute. And yet others hold that the Shmita has become purely voluntary. An analysis by respected Posek and former Sephardic Chief Rabbi Ovadiah Yosef in his responsa Yabi'a Omer (Vol. 10), accorded with the middle option, that the Biblical obligation holds only when a majority of the Jewish people is living in the Biblical Land of Israel and hence the Shmita nowadays is a rabbinic obligation in nature. This approach potentially admits for some leniencies which would not be possible if the Shemitah were biblical in origin, including the aforementioned sale of the land of Israel. Haredi authorities, on the other hand, generally follow the view of the Chazon Ish, that the Shmita continues to be a Biblical obligation.
The Sma, who holds that Shmitta nowadays is only a Rabbinic obligation, holds that the Biblical promise of bounty for those who observe the Shmitta (Leviticus 25:20-22) only applies when the Biblical obligation is in effect, and hence that the Biblical promise of bounty is not in effect today. However, the Chazon Ish, who holds that the Biblical obligation of Shmitta observance remains in effect today, holds that the Biblical promise of bounty follows it and Divine bounty is promised to Jews living in the Land of Israel today, just as it was promised in ancient times. However, he holds that Jews should generally not demand miracles from Heaven and hence that one should not rely on this promise for one's sustenance, but should instead make appropriate arrangements and rely on permissible leniencies.
Haredi Jews tell stories of groups of Israeli Jews who kept the Shmitta and experienced remarkable agricultural events which they describe as representative of miracles in fulfillment of the Biblical promise of bounty. One famous story is told about the then-two-year-old village of Komemiyut during the 1952 Shmittah. The village was one of the few who refrained from working the land that year. At the end of the Shmittah, farmers searching for seed to plant found only wormy, inferior seed that had been rotting for years in an abandoned shed. Rabbi Binyamin Mendelson advised them to sow this seed anyway, saying "The Almighty who causes wheat to sprout from good seed will bless your inferior seed as well," even though it was three months after neighboring villages had planted their fields. They did. That year the fall rains came late, the day after the Komemiyut seed was sown. As a result, the neighboring villages had a meager harvest, while the village of Komemiyut, who sowed from the old store, had a bumper crop.
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