“Remember the Sabbath day, to keep it holy. 9 Six days you shall labor and do all your work, 10 but the seventh day is the Sabbath of the Lord your God. In it you shall do no work: you, nor your son, nor your daughter, nor your male servant, nor your female servant, nor your cattle, nor your stranger who is within your gates. 11 For in six days the Lord made the heavens and the earth, the sea, and all that is in them, and rested the seventh day. Therefore the Lord blessed the Sabbath day and hallowed it.”
Word study
The word for work here is melakah מְלָאכָה from the root malak מֲלְאָךְ which means messenger. It is usually used in the context of a profession or occupation, including buying and selling (see Nehemiah 13:15-22) and is the same word used of YHWH when he rested from the work of creation in Genesis 2:2-3.