There is physical darkness and spiritual darkness. These distinctions are not theoretical.
During the Plague of Darkness, the first three days were darker than the darkest night. But the next three days were even darker, so dark that the darkness was palpable, preventing the Egyptians from moving. (Rashi on Exodus 10:22) This was not simply the absence of light, but a creation called "darkness" which has independent existence. "It was a thick darkness, meaning that a very thick mist came down from 'heaven.' For this is why G-d said to Moses, 'Stretch forth your hand toward the heavens' to bring down from there a great darkness...." (Ramban on Exodus 10:23)
Imagine being lost in the deepest cave. You cannot see your hand even an inch from your eyes. But at least you can move. Tangible darkness is beyond that, a heaviness which smothers all movement. The Talmud relates the word "choshech... darkness" to eternal death (Sanhedrin 24a) This is the state of one who has forfeited his share in the eternal light of Torah.
During the Plague of Darkness the terrible decree took effect in which eighty percent of the Children of Israel perished! Please contemplate this number; I don't know if we can appreciate the enormity of what happened here. This was a holocaust of galactic magnitude. The commentator Rashi uses extreme language to describe it. "There were among Israel of that generation wicked individuals - 'rashaim' - who did not wish to depart from Egypt, and they died during 'y'mai afaila,' the three days of gloom...." (Rashi on Exodus 10:22)
The ticket to oblivion seems to be "not wishing to depart from Egypt." Since everything the Torah tells us is for eternity, it becomes strikingly clear that we must learn from this to avoid at all costs becoming immersed in the host culture of exile. Even in the desert with Moses, we came close to collapsing under the onslaught of foreign culture. It was only the zealot Pinchas who saved the Children of Israel from the daughters of Midian! Otherwise, who could say what the end would have been!
When our own children were young, we used to let them watch cartoons after the Sabbath. I thought to buy a big-screen monitor, and so one day I walked into an electronics store in Borough Park. Across the counter, a chassidic salesman asked me, "When the Yetzer Hara (the Evil Inclination) is dancing in front of you, how big would you like it to be?"
Talk about embarrassment! "Mi k'amcha Yisroel, goy echad b'aretz... Who is like Israel, a unique nation!" (II Shmuel 7:23) This could only happen in a Jewish store where the legacy of Pinchas survives!
My friends, we have to be incredibly vigilant, because the dangers we face are indescribable. If four-fifths of the Children of Israel - and this was the generation of Moses! -was decimated because they clung to the foreign culture, then what about us! Ma'ase avos siman l'banim ... the actions of the fathers are a sign for the children! The Torah is warning us that there is a point at which the soul can be overcome by the blackness of "eternal death."
The Talmud (Berachos 11b) discusses how the Sages mandated that the characteristics of night be mentioned during the morning prayer and the characteristics of day be mentioned during the evening prayer. An Artscroll footnote explains that the rabbis were anxious to make a distinction between the Torah and, by contrast, various pagan beliefs in which light and dark were each considered a power in their own right. Our Rabbis say explicitly, "Blessed art Thou… G-d ... Who forms light and creates darkness."
Why did G-d create darkness?
Before Adam and Eve rebelled in the Garden of Eden, it was clear to them that there is only one reality. But the moment doubt entered their minds, they themselves "created" a new reality, the possibility - G-d forbid - that G-d is not the Sole Power in the universe. At Mount Sinai, G-d gave us the tool to regain our lost perception of Truth. But since we have free will and are able to "choose life," there must by definition also be an "alternative" to life, something else from which to choose!
In other words, by rebelling against G-d, mankind actually "necessitated" the creation of a new entity, called "afaila," palpable darkness that is both the embodiment of rebellion and the fate of those who choose it. That entity is what swallowed up those among the Children of Israel who cleaved to the culture of Egypt. G-d gave the Torah to those holy Jews who desired to come close to Him, and He gave afaila to those who chose to rebel.
The dangers of exile are beyond imagination, and Egypt is the archetypal exile. Its lessons are eternal. If we are to escape from this death trap, then we must absorb the lessons of these Torah portions. The allurements we face today are every bit as deadly as those we faced in Egypt. We must desperately desire to be among those who march out of exile with the Messiah. We must not allow ourselves to be swallowed up in the "afaila" that has imprisoned this world.
"Those who sat in darkness and the shadow of death, shackled in affliction and iron. Because they rebelled against the words of G-d and scorned the counsel of the Supreme One." (Psalm 107)
We have the option, my friends, to choose light or darkness. The Torah beckons!
"For the Jews there was light, gladness joy and honor! So may it be for us. I will raise the cup of salvations and I shall invoke the Name of G-d." (Megillas Esther/Havdallah prayer)