Rabbi Isaac taught that the words of Psalm , "mighty in strength that fulfill His word," speak of those who observe the Sabbatical year. Rabbi Isaac said that we often find that a person fulfills a precept for a day, a week, or a month, but it is remarkable to find one who does so for an entire year. Rabbi Isaac asked whether one could find a mightier person than one who sees one’s field untilled, see one’s vineyard untilled, and yet pays one’s taxes and does not complain. And Rabbi Isaac noted that uses the words "that fulfill His "word" (, "devar")," and says regarding observance of the Sabbatical year, "And this is the "manner" (, "devar") of the release," and argued that ""dabar"" means the observance of the Sabbatical year in both places.