Regarding the Ninth Plague: (Exodus) and per quote: rabbibuchwald.njop.org/2012/01/23/bo-5772-2012/
In Exodus 10:21, we read that G-d tells Moses, Stretch forth your hand toward the heavens, and there shall be darkness upon the land of Egypt, and the darkness will be palpable. When Moses stretches forth his hand toward the heavens,** a thick darkness appears throughout the land of Egypt for a three day period**. No man could see his brother, nor could anyone rise from his place for a three day period. But, for all the Children of Israel, there was light in their dwellings.
"the words “three days” appear twice in the verse, the plague of darkness lasted for at least six days. He notes, however, a difference between the first three days and the last three days. During the first three days there was a darkness of gloom, when “no man could see his brother.” During the second three day period, however, the Torah reports that “no man could rise from his place.”
"It may be argued that the plague of darkness should not be considered alone, but rather as joined with the final plague, death of the first born. Together, they constitute one plague–a plague of physical darkness followed by “ultimate” darkness, death.
Darkness, whether it strikes physically or metaphorically, is a most severe plague. To live in darkness is surely a very painful and lonely existence. May all good people be spared this plague and be enveloped in G-d’s light and beneficence."
Last thought: (Regarding the Exodus - Passover, and the Christ’s Passion)
**Mark 15:33, 33 At the sixth hour darkness came over the whole land until the ninth hour. 34 And at the ninth hour Jesus cried out in a loud voice, “Eloi, Eloi, lama sabachthani?”—which means, “My God, my God, why have you forsaken me?”
Again, there is more to this in regards to the hours, however, in regards to Peter denial, and the cock’s crow (shows the hour of the day) It was said that at the cock’s crow - was a sign of the half way mark to the redemption. When Peter denies our Lord – the Lord said to Peter, “Before a cock crows, you will deny Me three times.” - everything had to be done before the cock’s crow, the first sign of day light. (again, speculating on all this)
However, midnight (darkest part of the night) - Hebrew words kachatzot halailah, rendered above as at midnight, would read, as the night divides, (see Genesis 15 - the Covenant of the Halves, I use to think this had a lot to do with the dividing of the night and the redemption.)
On any other day, a priest would remove the ashes from the altar at about the time of the cock’s crow (in accordance with Leviticus 6:3). But for Yom Kippur, the ashes were removed beginning at midnight of the night before. Before the cock’s crow approached, Israelites filled the Temple Court. (Mishnah Yoma 1:8; Babylonian Talmud Yoma 20a.) The officer told the priests to see whether the time for the morning sacrifice had arrived. If it had, then the priest who saw it would call out, “It’s daylight!” (Mishnah Yoma 3:1; Babylonian Talmud Yoma 28a.)en.wikipedia.org/wiki/Acharei
The night in the Torah symbolizes suffering and exile. It is not only night, but it is the night of the night — midnight, the time of the deepest suffering and exile, when the voice of God seems silent.