Even as God wanted the Israelites to work six days and rest on the seventh day, called the Sabbath, which is our Saturday, so He wanted Israel to let the land enjoy a Sabbath every seven years,
“…but in the seventh year there shall be a sabbath of solemn rest for the land, a sabbath to the LORD. You shall neither sow your field nor prune your vineyard” (Leviticus 25.4).
God is all for work, for He did want Israel to work six days, but He is all for rest also, and He wanted to them to rest their bodies one day a week; likewise, He wanted them to work the land six years, and then let the land rest for one solid year!
We need rest to be able to work more, and evidently the land is the same way.
I heard it said about one of America’s presidents, but I was not able to find out which one, that he said something to this effect, “Do not ask me to do twelve months work in twelve months, but ask me to do twelve months work in eleven months,” meaning that he needed time off, and then he could do whatever needed to be done.
The land has that same requirement.
Farmers in the past practiced this, not necessarily as a way to keep the Law of Moses, but they understood that it helped to keep down pests, and the soil needed replenishing.