You will work six days.

There is simply no commandment here, and this is seen in most of the lists of mitzvot. This is a prelude to the commandment to rest on Shabbat, or at most, not the one that comes from the rule of doing (one who does work on Shabbat also violates this by nullifying doing. But one who works does not fulfill doing). It is true that some of the first ones saw this as a commandment. I remember that Prof. Yehuda Levi cited them in his book Sha'arei Talmud Torah.