sabbath
Sabbath means rest. The derivation of the word is Hebrew, and the idea of taking a day off from labor is written into the Hebrew scriptures, most notably in the Decalogue, or Ten Commandments.
Moreover, in Exodus 31:15 we learn that "Six days may work be done; but in the seventh is the sabbath of rest, holy to the LORD: whosoever doeth any work in the sabbath day, he shall surely be put to death." (KJV)