Mishneh Torah — Positive Mitzvot מצוות עשה, Chapter 155
The full Hebrew text of Mishneh Torah, Positive Mitzvot, Chapter 155, with English translation by Maimonides (Rambam).
לקדש שבת, שנאמר: "זכור את יום השבת, לקדשו" (שמות כ,ז).
To sanctify the Sabbath, as [Exodus 20:8] states: "Remember the Sabbath day to keep it holy."