6 The verb is usually translated “and sanctified it.” The Piel verb קִדֵּשׁ (qiddesh) means “to make something holy; to set something apart; to distinguish it.” On the literal level the phrase means essentially that God made this day different. But within the context of the Law, it means that the day belonged to God; it was for rest from ordinary labor, worship, and spiritual service. The day belonged to God.
7 Heb “God.” The pronoun (“he”) has been employed in the translation for stylistic reasons.
8 Heb “for on it he ceased from all his work which God created to make.” The last infinitive construct and the verb before it form a verbal hendiadys, the infinitive becoming the modifier—“which God creatively made,” or “which God made in his creating.”

In other versions

So God blessed the seventh day and made it holy, because on it God rested from all his work that he had done in creation.

Then God blessed the seventh day and made it holy, because on it he rested from all the work of creating that he had done.

God blessed the seventh day and declared it holy, for on it he rested from all his work of creation.

And God blessed the seventh day and declared it holy, because it was the day when he rested from all his work of creation.

And God blessed the seventh day, and he sanctified it, because on it he rested from all his work of creating that there was to do.

And God blessed the seventh day, and sanctified it: because that in it he had rested from all his work which God created and made.

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