And this is the idea of the Munn, that it spiritually came from the level called “the Dew from Above” (Initiative from Above), the level of “I Hashem never change” which is a level totally beyond time. It is for this reason that it had to be “every day just for that day”. Therefore, specifically “today (on Shabbos) you will not find it (the Munn) in the field”. This ‘field’ is referring to the physical world that has six directions, up-down, east-west, north-south”.
Why? “Because this is a day of Shabbos/Rest for Havaya.” Meaning, that the level of Hashem’s revelation called Havaya also has ‘rest’ on Shabbos, since it returns to its source in Hashem how He is beyond being a source for the world. Rather, on Shabbos “then you will have pleasure עַל הֲוָיָ"ה -on Havaya”, meaning from a level above Havaya, which is the Initiative from Above that is not dependent on our Initiative from Below.
Hashem’s true desire (פנימיות רצון העליון) is only for holiness, and particularly the divine service of the Jewish People. In Tanya (chapter 6 and chapters 22-25) the Alter Rebbe explains that all unholiness comes from the external aspect of His will (אחוריים של רצון העליון). He doesn’t want it for its own sake, but only in order that we have free will to serve Him of our own volition, but otherwise He doesn’t want unholiness to exist at all. The opposite is true of holiness, that Hashem truly desires us and our service for its own sake, not because of something else. Only below in the world are there these two aspects of Hashem’s desire, His innermost desire is expressed in creating and giving life to holiness, and His external desire that creates and gives life to unholiness. However, on a level beyond the existence of this world there is only His Innermost Will for holiness.
Therefore, on Shabbos when “Hashem lifts up Havaya” to its source beyond the creation of the world, we are able to receive from a level where only His Innermost Desire in holiness is expressed. This also affects the food we eat on Shabbos; it receives from a level where there is no room for unholiness to exist, and therefore the food doesn’t need spiritual refinement.
