God's command to Moshe about Shabbat at the end of the instructions for building the mishkan
Moshe begins his set of guidelines to B'nai Yisrael regarding the mishkan with the mitzva of Shabbat:
וַיֹּ֣אמֶר מֹשֶׁ֔ה אֶל־כׇּל־עֲדַ֥ת בְּנֵֽי־יִשְׂרָאֵ֖ל לֵאמֹ֑ר זֶ֣ה הַדָּבָ֔ר אֲשֶׁר־צִוָּ֥ה יְהֹוָ֖ה לֵאמֹֽר׃ קְח֨וּ מֵֽאִתְּכֶ֤ם תְּרוּמָה֙ לַֽיהֹוָ֔ה כֹּ֚ל נְדִ֣יב לִבּ֔וֹ יְבִיאֶ֕הָ אֵ֖ת תְּרוּמַ֣ת יְהֹוָ֑ה זָהָ֥ב וָכֶ֖סֶף וּנְחֹֽשֶׁת׃
"On the literary level, the verses dealing with Shabbat serve to return the narrative to the flow of events which had been disrupted by the golden calf. The mitzva of Shabbat immediately reminds the reader of God's discussion of Shabbat which occurred just prior to the sin of the golden calf, thus restoring the narrative flow...
Granted, God and Moshe need to warn the workers that the construction of the mishkan would not override the prohibitions of Shabbat. But this reminder could have been expressed in just a few words. Why does the Torah invest so much text to the laws of Shabbat observance? Although the people had already been instructed with regard to Shabbat observance both in Midbar Sin (in the context of the manna) and again at Mt. Sinai (in the fourth of the Ten Commandments), God spends six verses telling Moshe about Shabbat at the conclusion of His remarks regarding the construction of the mishkan. Why?"
A. "Remember the Shabbat day and keep it holy."
B. "Six days you shall labor and do all your work, but the seventh day is a Shabbat of Hashem your God"
C. "You shall not do any work - you, your son or daughter, your male or female servant, or your cattle, or the stranger who is within your settlements."
B. "For in six days God made heaven and earth and sea, and all that is in them, and He rested on the seventh day."
A. "Therefore, God blessed the Shabbat day and sanctified it."
" This structure of the Fourth Commandment clearly associates the individual's observance of Shabbat with that of the Almighty. At Mt. Sinai, God stresses man's obligation to follow God's lead and sanctify the day of Shabbat."
Shabbat at the end of Mishpatim:
But Shabbat at Sinai has a societal focus: Shabbat is so your workers can REST.
The two other references to the mitzvah of Shabbat are taught in the context of the building of the mishkan:
Rav Yoni explains that in the context of the mishkan, we have two new elements added: chillul and karet: " One who fails to observe the Shabbat has not only VIOLATED a commandment, but has DESECRATED the Shabbat. The Shabbat is to be viewed as a sacred entity, and thus neglect of its laws result in a desecration of its sacred quality. This concept - the inherent sanctity of Shabbat - appears for the first time in this context, in association with the mishkan."
"The kedusha of Shabbat, as described by the first half of the parasha, is manifest in three ways:
A. God sanctifies Benei Yisrael: "for I am Hashem Who sanctified you."
B. Benei Yisrael sanctify the Shabbat: "You shall keep the Shabbat, for it is holy for you."
C. God Himself sanctifies the Shabbat: "a Shabbat of complete rest, holy to God."
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Thus, Shabbat is holy both for God and the Jewish people, and, consequently, Benei Yisrael become a sacred people in the eyes of God. In other words, God, in order to sanctify the people, presents them with His unique gift, an item of ultimate sanctity to Him. The moment they, too, sanctify the Shabbat, they become sacred before the One Who had sanctified the Shabbat in the first place - God. Through the Shabbat, which is sanctified to both God and Benei Yisrael, Benei Yisrael become a holy nation before the Almighty.
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In parashat Vayakhel, as Moshe recounts God's commandment regarding the Shabbat, he includes both elements of the sanctification of the Shabbat: "On six days work may be done, but the seventh day shall be holy for you, a Shabbat of complete rest to God; whoever does any work on it shall be put to death" (Shemot 35:2). The seventh day will be "holy for you," for it is a "day of complete rest to God." Based on the lengthier commandment he heard from God, Moshe incorporates both sources of the sanctity of Shabbat in his monologue to the people.
"God's discussion of Shabbat, with which He concludes His guidelines regarding the mishkan, combines the two different functions of Shabbat - the testimony to God's having created the world, and the more "intimate" quality of Shabbat - the unique, sacred relationship between the Almighty and His people"
Mishkan= sacred space
Shabbat= sacred time
Shabbat melachot based on the Mishkan's melachot because the Mishkan helped B'nai Yisrael comprehend sanctity inherent in something ( a space), which must be protected from desecration.- and so the concept of how to keep Shababat(inherently sacred time) holy is derived from the model of the Mishkan.
