“Sabbath of complete rest.” The Hebrew is shabbath shabbathon, more literally, “a Sabbath of Sabbath observance.” This is to be understood as a Sabbath in which there is Sabbath observance, or a Sabbath of complete rest (cp. “complete rest,” CJB; HCSB; NAB; NET; NLT). This Hebrew phrase occurs six times in the Bible: Exodus 31:15, 35:2; Leviticus 16:31; 23:3, 32, and here in Leviticus 25:4.

God rested on the seventh day in Genesis 2:1-3, but He did not command that anyone follow His example and rest on the seventh day until Exodus 16, when He gave the manna from heaven, and even then He did not fully explain the Sabbath. The Sabbath became part of the Law and the Old Covenant when it was given as part of the Ten Commandments (Exod. 20:8-11).

[For more on the Sabbath, see commentary on Exod. 20:10.]