לעשות את השבת, “to observe the Sabbath actively.” The plain meaning of this line is: “to provide himself with the necessities required on the Sabbath.” The expression לעשות is found in this context in Genesis 18,7 and 18,8 where the Torah reports Avraham as preparing the luncheon for the three angels who had come to visit him. The basic meaning of the verse is to encourage people to prepare for the Sabbath in time so that they can enjoy the day when it occurs. Our sages (Beitzah 16) understand the exhortation to mean that one is to plan from one Sabbath for the next, and that this is the implied meaning of the prophet (Isaiah 58,13) who said: “you shall call the Sabbath ‘a delight.’” When the prophet employed the word וקראת in that verse, as if one were to “call towards the Sabbath,” he meant we should “invite the Sabbath” as one invites guests to one’s table. A Midrashic approach: anyone observing the Sabbath properly on terrestrial earth is considered as if he had “made” it in the celestial regions. What is meant by this Midrash (Mechilta Ki Tissa) is that keeping the Sabbath is testimony that a person is a true believer in G’d and His Torah. Anyone who ignores the laws of the Sabbath thereby testifies that he is an heretic and does not believe. This is also why the word לעשות was used here instead of the more common לשמור אותה. The Torah wanted to allude to the fact that Sabbath observance is a concept which also exists in the celestial regions.

ושמרו בני ישראל, “The Children of Israel shall observe, etc,;” they shall have in mind the next Sabbath during the six working days, looking forward to it, and to prepare for it in order not to need to desecrate it when it comes. This expression was mentioned earlier in v. 14; it is repeated here on account of it having to match the expression ברית עולם, “an everlasting covenant.”

The addition of the word אותה in the line עשו אותה, testifies to the quality of the work. The artisans had put to use all their intelligence in constructing these parts and the result had proved successful.