Charles Ellicott Commentary Exodus 34:21

"Six days thou shalt work, but on the seventh day thou shalt rest: in plowing time and in harvest thou shalt rest." — Exodus 34:21 (ASV)

The law of the Sabbath meets us at every turn in Exodus. It was so fundamental to the entire polity, that it naturally held a place in every section of the legislation.

We have already found it:

1. Propounded at the giving of the manna (Exodus 16:22–30).
2. Reasserted in the fourth commandment (Exodus 20:8–11).
3. Introduced into the “Book of the Covenant” (Exodus 23:12).
4. Appended to the directions given for the construction of the Tabernacle (Exodus 31:13–17).

In earing time and in harvest thou shalt rest. —“Earing-time” is plowing time; “to ear” is an old English verb, etymologically connected with the Greek ἄρω and the Latin aro. (Deuteronomy 21:4; 1 Samuel 8:12; Isaiah 30:24.) There was a special temptation to encroach upon the Sabbatical rest at the times most critical in respect to agricultural operations.