God said otherwise:
Exo 20:8 Remember the sabbath day, to keep it holy.
Exo 20:9 Six days shalt thou labour, and do all thy work:
Exo 20:10 But the seventh day is the sabbath of the LORD thy God: in it thou shalt not do any work, thou, nor thy son, nor thy daughter, thy manservant, nor thy maidservant, nor thy cattle, nor thy stranger that is within thy gates:
Exo 20:11 For in six days the LORD made heaven and earth, the sea, and all that in them is, and rested the seventh day: wherefore the LORD blessed the sabbath day, and hallowed it.
God blessed nothing, neither hallowed anything in Exodus 20:1-17. It is only in Genesis 2:1-3, that God did so, and only then did God rest, in the 7th day. God specifcally calls that day, by his own voice and finger, "the sabbath day". The verb becomes the noun not becaue I said so, but because God said so.