Parshat Vaeira

Bereishit 6:3
I appeared to Abraham, Isaac, and Jacob as El Shaddai, but I did not make Myself known to them by My name LORD.
We have to explain the sequence as follows: “Although I have revealed Myself to the patriarchs as the attribute of Shaddai, My principle name, the one that represents My essence,” [is LORD]
Chagigah 12a
When the Holy One, Blessed be He, created the world, it continued to expand like two balls of warp, whose cord lengthens as they unravel, until the Holy One, Blessed be He, rebuked it and made it stand still … Reish Lakish said: What is the meaning of that which is written: “I am the Almighty God [El Shaddai]” (Genesis 17:1)? It means I am He who said to said to the world “enough [dai],” instructing it to stop expanding.
El Shaddai represents God as the master of natural forces. The four-letter name of God is more fundamental, God as Existence or Being.
Rabbi Yehudah Leib, Alter of Ger
Every bit of truth is surrounded by falsehood on all sides. Nevertheless, by means of struggle, the point of truth can be found in every place. This was the holy work of our forefathers. 
Moses merited seeing things as they will be in the future: One God and His name One. Then there will be nothing but the divine life-force. But in this world everything is garbed in nature. It is by sanctifying yourself in this-worldly matters that you attain some bit of understanding. … But this is hard word, that task that we do through the week. The holy Sabbath is the lucid glass, when there is an abundance of revelation …
“Wisdom is great, but knowing is still greater. To the one He loves He gives a morsel from His own mouth.” … knowing is an intimate attachment; it is knowing in your very soul. 
So the world and all within it are witnesses to the blessed Holy One. Even the Sages among the gentiles have to bear witness to the Creator; the natural scientist surely sees the Creator’s wonders.
But of Israel it is written: “You have been shown knowledge,” we are witnesses both by seeing and by knowing. We attained this when we came out of Egypt and received the Torah, of which Scripture says: “Let him kiss me with the kisses of his mouth.”
Hearing requires being empty of every thing.
Each day we say: “Hear, O Israel, the LORD is our God, the LORD is One”; this is the voice saying, “I am the LORD your God”; it has never stopped. But we have to prepare ourselves to truly hear the Shema without any distracting thought. 
That is why we mention Exodus before the Shema. By being redeemed from Egypt we are emptied of all distraction and become ready to hear God’s word.
Bereishit 9:12
But the LORD stiffened the heart of Pharaoh, and he would not heed them, just as the LORD had told Moses.
Bereishit 9:27
[After the plague of hail] Thereupon Pharaoh sent for Moses and Aaron and said to them, “I stand guilty this time. the LORD is right, and I and my people are in the wrong.”
Bereishit 9:34-35
But when Pharaoh saw that the rain and the hail and the thunder had ceased,  he became stubborn and reverted to his guilty ways, as did his courtiers. So Pharaoh’s heart stiffened and he would not let the Israelites go, just as the LORD had foretold through Moses.
Ibn Ezra
Know that the Divine decree underlies all actions and all phenomena, in the sense that the nature and potentiality of everything in the universe, including living creatures, is determined by the action of the constellations on the four elements [i.e., on natural law]. A creature’s behavior at every moment is governed by its nature and its potential.  However, as the author of the Sefer Yesira has explained, a certain deviation can exist. Individuals derive their nature from the species, and they can change their nature within the boundaries of their species’s potential. This is the meaning of “God hardened the heart of Pharaoh” (Exodus 9:12), although elsewhere Scripture asserts, “he hardened his [own] heart; he and his officials” (Exodus 9:34). Both statements are true.
it is foolish to ask how God could punish Pharaoh after he Himself had interfered with his decision-making process by “stiffening his heart, I will stiffen the heart of Pharaoh” not in order to punish him but in order to finally trigger repentance in his heart.
Mark Twain [as cited by Adin Steinsaltz]
To cease smoking is the easiest thing I ever did. I ought to know because I’ve done it a thousand times.
Rabbi Adin Steinsaltz
One of the basic questions about Pharaoh’s character is why, after suffering blow after blow, does he not respond? Granted, the Torah states that “God harden Pharaoh’s heart”; still this raises the question of what underlies this whole situation.
In the course of the ten plagues, Pharaoh goes through a process of change in his fundamental conception of his own life … it occurs to him that perhaps his whole life has been a great lie.
… Pharaoh’s experience exists in other people’s experiences as well when, as a result of repenting for a certain act, they suddenly discover an entirely new way of thinking in which everything has a completely different significance.
True repentance may require someone to question their entire value system and way of life. This awareness, and acting on it, may be very difficult to reach and sustain. People may employ all sorts of mental tricks to deny the truth they have briefly seen.