Va'erah: The Science of Revelation

The parsha opens with Gd declaring to Moshe that this is the same Gd who appeared to the patriarchs. This is a statement of constancy. To a degree, this action is prompted by the interaction in the last parsha, when Moshe requests the name, an identifier, that makes communication possible.  The Gd that will liberate the Israelites from Egypt is not a new entity. Gd is the same entity that promised Abraham a reward for his obedience and courage; the Gd that rescued Isaac from the fervor of his righteous father when Abraham  brought him as a sacrifice; the same Gd that rescued Jacob from the wrath of his brother Esau and granted his clan safe passage into the Promised Land. Something spectacular is now promised and it is going to happen, but it is not disconnected from the birth of this people

Va'erah is not merely the key word in the first few verses, it is also the theme of the parsha.  Gd makes a public display of Divine power.   Previously,  an appreciation of Gd's role in the world was limited to those who would accept it, the patriarchs, Abraham, Isaac and Jacob.  I think this could have been Rashi's intention when he  wrote:

וארא. אֶל הָאָבוֹת:

וארא AND I APPEARED — to the patriarchs. on a verse that reads: 

וָאֵרָ֗א אֶל־אַבְרָהָ֛ם אֶל־יִצְחָ֥ק וְאֶֽל־יַעֲקֹ֖ב בְּאֵ֣

I appeared to Abraham, Isaac, and Jacob as El Shaddai, but I did not make Myself known to them by My name

Rashi reminds us that in the time of patriarchs, they were the only ones who appreciated events in their lives (some of which were world events) as Divine intervention from the One Gd. 

It now becomes important to connect to that One Gd because Gd will now reveal much more of Gd's power to the Egyptians, the enslaved Israelites and the world.  This is the big וָאֵרָ֗א  , revelation. 

The plagues are a progressive exhibition of Gd's authority and might. Their several purposes are stated

וְלֹֽא־יִשְׁמַ֤ע אֲלֵכֶם֙ פַּרְעֹ֔ה וְנָתַתִּ֥י אֶת־יָדִ֖י בְּמִצְרָ֑יִם וְהוֹצֵאתִ֨י אֶת־צִבְאֹתַ֜י אֶת־עַמִּ֤י בְנֵֽי־יִשְׂרָאֵל֙ מֵאֶ֣רֶץ מִצְרַ֔יִם בִּשְׁפָטִ֖ים גְּדֹלִֽים׃ 

When Pharaoh does not heed you, I will lay My hand upon Egypt and deliver My ranks, My people the Israelites, from the land of Egypt with extraordinary chastisements.

וְיָדְע֤וּ מִצְרַ֙יִם֙ כִּֽי־אֲנִ֣י יְ

And Miżrayim shall know that I am the Lord

The primary purpose of the plagues is to deliver the Israelites from the land of Egypt.  The שְׁפָטִ֖ים גְּדֹלִֽים, the great demonstrations of justice, are a broader message to Israel and all the world. Some of the  plagues are easily seen as redress for the attitudes and behaviors of the Egyptian masters. In the plague of blood, the Nile regurgitates the blood of the Hebrew male infants that Pharaoh had ordered drowned in it. The frogs are a manifestation of how the Egyptians felt about the Hebrews: they were obnoxiously everywhere, intercalating themselves into society, having excessive numbers of children. The Hebrews made the Egyptians' skin crawl, like a lice infestation. 

The battle of the staves is confusing. Aaron throws down his staff and it turns into a serpent. This appears to be a well known trick, so the wise men and sorcerers do likewise. Aaron's staff eats the other staves. The story is demonstration of Aaron's, hence Moshe's, hence Gd's, greater power. The the staff  is subsequently used to initiate many of the plagues. Did Aaron's magic wand gain additional magical powers from the the wands that it swallowed?  Certainly, we do not believe this, so the story becomes a demonstration of the absurdity of magic. But a magic devotee could see it differently. Aaron's staff was fortified by the staves that it swallowed and the magicians lost some their power .  The story allows alternative explanations. The parsha tries to direct us to the One Gd as the director of all events. 

The parsha ends with the seventh plague: hail. Hail is a meteorological event, a "natural" phenomenon.  To me, hail is a reminder of the miracle  that the earth is generally blessed with gentler forms of precipitation: rain and snow. Ice, solid water,  comes in many forms depending upon the pressure and temperature under which it forms ( there is not ice 9, Vonnegut's world destroying contagious ice). [ I used to tell my children, when they were small, stories  about a planet, named Dorton, on which the precipitation was large chunks of ice.]. 

The plague of hail is introduced by disclosing another purpose for these plagues

וְאוּלָ֗ם בַּעֲב֥וּר זֹאת֙ הֶעֱמַדְתִּ֔יךָ בַּעֲב֖וּר הַרְאֹתְךָ֣ אֶת־כֹּחִ֑י וּלְמַ֛עַן סַפֵּ֥ר שְׁמִ֖י בְּכׇל־הָאָֽרֶץ׃ 

Nevertheless I have spared you [Pharaoh] for this purpose: in order to show you My power, and in order that My fame may resound throughout the world.

 Gd warns  the Egyptians that they need to go inside during the plague of hail. This warning  demonstrated  the universal message of the necessity of  believing the word of Gd and acting upon it.   Those that feared Gd, brought their slaves and cattle indoors. Those that did not , left them outside and they were killed.

Science  does not explain everything. Magic cannot be trusted. The appreciation of everyday  miracles requires openness and  education. It can save your life.