פרשת בהר - בחקותי תש"ה - שמיטה

As to the precepts enumerated in the laws concerning the year of release and the jubilee (Hilkot shemittah ve-yohel) some of them imply sympathy with our fellow-men, and promote the well-being of mankind; for in reference to these Precepts it is stated in the Law, "That the poor of thy people may eat" (Exod. 23:11); and besides, the land will also increase its produce and improve when it remains fallow for some time. Other precepts of this class prescribe kindness to servants and to the poor, by renouncing an claims to debts [in the year of release] and relieving the slaves of their bondage [in the seventh year]. There are some precepts in this class that serve to secure for the people a permanent source of maintenance and support by providing that the land should remain the permanent property of its owners, and that it could not be sold." And the land shall not be sold for ever" (Lev. 25:23). In this way the property of a person remains intact for him and his heirs, and he can only enjoy the produce thereof. I have thus explained the reason of all precepts contained in our work in the Section Zera‘im, with the exception of the laws concerning the intermixture of different species of beasts the reason of which will be given (chap. xlix.).

It is a positive commandment to refrain from working the land and caring for trees in the seventh year, as it says, "and the land shall rest a Sabbath for the Lord" (Leviticus 25:2), and it says "in plowing and in harvesting you shall rest" (Exodus 34:21). Anyone who performs one of the forbidden labors from the working of the land or caring for trees in this year has abrogated a positive commandment and transgressed a negative commandment, as it says, "you shall not plant your field, nor shall you prune your vineyard" (Leviticus 25:4).