That we not work the land on the seventh year: That we not work the land on the seventh year, which is called the sabbatical (shemittah) year, as it is stated (Leviticus 25:4), “But on the seventh year, etc. your field you shall not sow.”

The root of this commandment, its details and all of its content is written in Eem Kessef Talveh (Sefer HaChinukh 84) — take it from there. And one who transgresses it and works the land at the time of the [Temple] with one of the types of work that are forbidden from Torah writ — as we [explained] over there — is lashed.