Shemos: 12: 29. It came to pass at midnight, and the Lord smote every firstborn in the land of Egypt, from the firstborn of Pharaoh who sits on his throne to the firstborn of the captive who is in the dungeon, and every firstborn animal.
Here we are in the land of darkness itself. It is a place where Paro has been proclaimed ruler over all including having the power of life and death. It is the place where negativity reigns supreme oblivious it would seem to even the faintest inkling of the light. However it is the light itself ironically that comes through this place to take away the most precious of all; the first born throughout the entire land.
These first-born are an allusion to those thoughts that have come from the other side that has been the foundation of sustaining that state of being or mind known as Mitzrayim.
These thoughts are the offspring of negativity and they cannot be nurtured from within or by association, as is the case with thoughts that are born of the light. They derive their energy by feeding off of the light by degrading it or in the case of Israel enslaving them.
If we take this analogy further these first born of Mitzrayim are synonymous with the klippoth those shells of discarded awareness that were the result of the shattering of the vessels in the beginning.
Each plague represented a taking away of one more avenue of sustenance until at last their very essence was eliminated completely. Paro calls Moshe to tell him to leave and to give him a blessing because Paro himself is also a first-born child.
Shemos: 12: 32. Take also your flocks and also your cattle, as you have spoken, and go, but you shall also bless me.”
Now contrast what is happening here to the first-born of Mitzrayim as to what Hashem has planned for the first-born of Israel.
Shemos: 13: 2. “Sanctify to Me every firstborn, every one that opens the womb among the children of Israel among man and among animals; it is Mine.”
The firstborn of Israel are sacred to Hashem. They represent a higher level of thought which is free and holy in that it emanates because of Hashem and because of our attention and service to Hashem. Call it the good intention if you will that seeks the service of mitzvah in order reinforce that connection above always listening. Even before Sinai and the giving of Torah these thoughts or firstborn are declared for Hashem. This will set the stage for the giving of Torah as we shall see in the next few parashiyot.
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