Deutéronome 5:12

שמור OBSERVE [THE SABBATH DAY] — But in the former Ten Commandments (i.e. where they were first promulgated, in Exodus XX.), it states, “Remember [the Sabbath day]"! The explanation is: Both of them (זכור and שמור) were spoken in one utterance and as one word, and were heard in one hearing (i.e. were heard simultaneously) (Mekhilta). כאשר צוך [OBSERVE THE SABBATH DAY TO SANCTIFY IT] AS [THE LORD THY GOD] COMMANDED THEE before the giving of the Law, at Marah (Shabbat 87b).

Keep the sabbath day to sanctify it, as the Lord thy God has commanded thee.

שָׁמ֛֣וֹר אֶת־י֥וֹם֩ הַשַּׁבָּ֖֨ת לְקַדְּשׁ֑֜וֹ כַּאֲשֶׁ֥ר צִוְּךָ֖֣ ׀ יְהֹוָ֥֣ה אֱלֹהֶֽ֗יךָ׃