וְ֠הָיָה אִם־שָׁמֹ֨עַ תִּשְׁמְע֤וּן אֵלַי֙ נְאֻם־יְהוָ֔ה לְבִלְתִּ֣י ׀ הָבִ֣יא מַשָּׂ֗א בְּשַׁעֲרֵ֛י הָעִ֥יר הַזֹּ֖את בְּי֣וֹם הַשַּׁבָּ֑ת וּלְקַדֵּשׁ֙ אֶת־י֣וֹם הַשַּׁבָּ֔ת לְבִלְתִּ֥י עֲשֽׂוֹת־בה [בּ֖וֹ] כָּל־מְלָאכָֽה׃
דרום װעט זײַן: אױב צוהערן װעט איר צוהערן צו מיר, זאָגט גאָט, ניט אַרײַנצוברענגען קין משׂא אין די טױערן פֿון דער דאָזיקער שטאָט אין טאָג פֿון שבת, נײַערט צו האַלטן הײליק דעם טאָג פֿון שבת, ניט צו טאָן אין אים קײן שִם אַרבעט,
Rabbeinu Bahya
A Kabbalistic approach: The words זכור את יום השבת are a reminder that the Sabbath is the last emanation seeing that it completes the whole cycle of creation. It has been named כנסת ישראל. Our sages (Bereshit Rabbah 11,8) have illustrated this by saying that the Sabbath is the natural partner of the Jewish people (much as a woman is the natural partner of man). This is the reason we find the Sabbath referred to in much of aggadic literature as Matrona, “a lady of stature.”
We find the following in Vayikra Rabbah 27,10: “The reason the Torah legislates that no animal may be offered up as a sacrifice until it is at least seven days old (Leviticus 22,27) is because it must first have seen the face of the Matrona. The Midrash means that an animal which has not experienced at least one Sabbath on earth must not be slaughtered as an offering. Even the life of an animal would not have been worth living unless it had experienced at least one Sabbath.
The Sabbath is also known as ברית, covenant. Just as the circumcision and the rainbow are described by the Torah as ברית, so is the Sabbath (compare Genesis 9,12--Genesis 17,10--Exodus 31,16). The reason the Torah writes here זכור, “to remember” is a reference to a specific Sabbath, i.e. the Sabbath known as שבת הגדול, the emanation יסוד, from which all the 248 positive commandments emanate. The numerical value of the letters in the word זכור plus the acrostic formed by the first letters in the words יום השבת total 248. When the Torah writes שמור את יום השבת in the second version of the Ten Commandments in Deut. 5,12, the word שמור is a reference to the מקדש, Sanctuary, aspect of the Sabbath. This is the emanation כבוד from which the 365 negative commandments are derived. They are the ones that also all women are obligated to fulfill. This is the mystical dimension of the verse את שבתותי תשמורו ומקדשי תיראו, “you shall observe My Sabbath days and My Sanctuary you shall revere” (Leviticus 26,2) [the plural My Sabbaths refers to the שבת הגדול and to the Sabbath called מקדש.] This is why the prophet warns (Jeremiah 17,24) “not to perform any kind of work on it.” The word בה “on it,” in that verse is read one way and spelled another, i.e. it is both בו and בה, i.e. masculine and feminine. When the Torah writes in verse 10 of our chapter ויום השביעי שבת לה' אלו-היך, “and the seventh day is a Sabbath for the Lord your G’d,” the meaning is that “the Sabbath is on the seventh day because the seventh day is the foundation (יסוד) of the universe the seventh emanation the one wherein the Sabbath (the concept of the Sabbath) is located.” Our sages referred to this as הכל בכל, “for that which comprises everything (כל) is contained within the emanation known as כל, respectively יסוד. The two emanations יסוד and מלכות are inseparably linked to one another. [The seventh day represents יסוד, which is described here as the seventh emanation. Since the concept of Sabbath (associated with מלכות) is contained in יסוד, it follows that the two are linked together. Ed]
We find verses which confirm this in Exodus 31,15: וביום השביעי שבת שבתון קודש לה', “and on the seventh day, which is the Sabbath, the Sabbath of Sabbaths, it is holy to Hashem.” The verse following the above states לעשות את יום השבת ברית עולם, “to make the Sabbath-day into an eternal covenant.” The verse refers to the seventh day which is the foundation of the universe שבת שבתון קודש לה'. At the same time the Sabbath which receives its input from that שבת שבתון is called ברית. Having appreciated all this there is no longer any reason to wonder why the sages called the benediction we recite over the wine on the Sabbath by day קדושא רבא, “the great sanctification,” (Pesachim 106) a description which has not been applied to the Kiddush we recite on the evening after the Sabbath has commenced. The Kiddush recited by day corresponds to the זכור element of the Sabbath whereas the Kiddush we recite at night corresponds to the שמור element of the Sabbath. Day is usually associated with זכור something denoting activity, whereas night is associated with שמור, something denoting passivity.
Considering all we have said above it is clear why the prophet considers the Sabbath a delight and called it such (Isaiah 58,13) “and you shall call the Sabbath a delight.” It is a delight for the souls. David confirmed this in Psalms 42,3 when he exclaimed צמאה נפשי לאלו-הים א-ל חי, “my soul thirsted after the living G’d.” Every creature thirst (yearns) after its origin, its roots, the place it will eventually return to. The place in question is the river which irrigates Gan Eden, the foundation of the Sabbath and its root. The word ענג, delight, is an acrostic formed by the words עדן, נהר, גן. We base all this on Genesis 2,10 ונהר יוצא מעדן להשקות את הגן “and a river emerges from Eden to irrigate the garden.” This is why the Sabbath is called ענג, as it is a delight both for the celestial beings as well as for the terrestrial people on earth.
We find the following in Vayikra Rabbah 27,10: “The reason the Torah legislates that no animal may be offered up as a sacrifice until it is at least seven days old (Leviticus 22,27) is because it must first have seen the face of the Matrona. The Midrash means that an animal which has not experienced at least one Sabbath on earth must not be slaughtered as an offering. Even the life of an animal would not have been worth living unless it had experienced at least one Sabbath.
The Sabbath is also known as ברית, covenant. Just as the circumcision and the rainbow are described by the Torah as ברית, so is the Sabbath (compare Genesis 9,12--Genesis 17,10--Exodus 31,16). The reason the Torah writes here זכור, “to remember” is a reference to a specific Sabbath, i.e. the Sabbath known as שבת הגדול, the emanation יסוד, from which all the 248 positive commandments emanate. The numerical value of the letters in the word זכור plus the acrostic formed by the first letters in the words יום השבת total 248. When the Torah writes שמור את יום השבת in the second version of the Ten Commandments in Deut. 5,12, the word שמור is a reference to the מקדש, Sanctuary, aspect of the Sabbath. This is the emanation כבוד from which the 365 negative commandments are derived. They are the ones that also all women are obligated to fulfill. This is the mystical dimension of the verse את שבתותי תשמורו ומקדשי תיראו, “you shall observe My Sabbath days and My Sanctuary you shall revere” (Leviticus 26,2) [the plural My Sabbaths refers to the שבת הגדול and to the Sabbath called מקדש.] This is why the prophet warns (Jeremiah 17,24) “not to perform any kind of work on it.” The word בה “on it,” in that verse is read one way and spelled another, i.e. it is both בו and בה, i.e. masculine and feminine. When the Torah writes in verse 10 of our chapter ויום השביעי שבת לה' אלו-היך, “and the seventh day is a Sabbath for the Lord your G’d,” the meaning is that “the Sabbath is on the seventh day because the seventh day is the foundation (יסוד) of the universe the seventh emanation the one wherein the Sabbath (the concept of the Sabbath) is located.” Our sages referred to this as הכל בכל, “for that which comprises everything (כל) is contained within the emanation known as כל, respectively יסוד. The two emanations יסוד and מלכות are inseparably linked to one another. [The seventh day represents יסוד, which is described here as the seventh emanation. Since the concept of Sabbath (associated with מלכות) is contained in יסוד, it follows that the two are linked together. Ed]
We find verses which confirm this in Exodus 31,15: וביום השביעי שבת שבתון קודש לה', “and on the seventh day, which is the Sabbath, the Sabbath of Sabbaths, it is holy to Hashem.” The verse following the above states לעשות את יום השבת ברית עולם, “to make the Sabbath-day into an eternal covenant.” The verse refers to the seventh day which is the foundation of the universe שבת שבתון קודש לה'. At the same time the Sabbath which receives its input from that שבת שבתון is called ברית. Having appreciated all this there is no longer any reason to wonder why the sages called the benediction we recite over the wine on the Sabbath by day קדושא רבא, “the great sanctification,” (Pesachim 106) a description which has not been applied to the Kiddush we recite on the evening after the Sabbath has commenced. The Kiddush recited by day corresponds to the זכור element of the Sabbath whereas the Kiddush we recite at night corresponds to the שמור element of the Sabbath. Day is usually associated with זכור something denoting activity, whereas night is associated with שמור, something denoting passivity.
Considering all we have said above it is clear why the prophet considers the Sabbath a delight and called it such (Isaiah 58,13) “and you shall call the Sabbath a delight.” It is a delight for the souls. David confirmed this in Psalms 42,3 when he exclaimed צמאה נפשי לאלו-הים א-ל חי, “my soul thirsted after the living G’d.” Every creature thirst (yearns) after its origin, its roots, the place it will eventually return to. The place in question is the river which irrigates Gan Eden, the foundation of the Sabbath and its root. The word ענג, delight, is an acrostic formed by the words עדן, נהר, גן. We base all this on Genesis 2,10 ונהר יוצא מעדן להשקות את הגן “and a river emerges from Eden to irrigate the garden.” This is why the Sabbath is called ענג, as it is a delight both for the celestial beings as well as for the terrestrial people on earth.
Radak
If You will surely look (lit., look, you will look): They expounded because of the doubling (of the word, look). But it is not necessary, for this is the way of the language, to join the infinitive with verbs, like (Jeremiah 17:24), "if you will surely listen (lit., listen, you will listen). And it said [it], because this combination is to strengthen the matter. And they, may their memory be blessed, expounded about it (Berakhot 31b), "If You will look, fine; but if not, You will look: I will go and have Elkanah, my husband, be jealous of me, and I will give birth, as You have written in Your Torah, (Numbers 5:28), 'But if the woman was not defiled and she is pure [... and shall bear seed].'"