Can you please explain the significance and the situation of this quotation from Macbeth:
Act II, Scene IV of Macbeth begins a few days after the events of Scene III. So, it is a few days after Macbeth has killed Duncan. Ross is speaking to an old man about the events that have transpired from the time of the murder to the present moment. Ross addresses him as "good father," a general way of addressing an older man. The old man begins the scene by saying that in all the 70 years of his life, he has never seen things so strange, dark and threatening:
Threescore and ten I can remember well,
Within the volume of which time I have seen
Hours dreadful and things strange, but this sore night
Hath trifled former knowings. (II.iv.1-4)
Ross agrees, saying that it is daytime but "dark night strangles the travelling lamp." Night obscures the sun ("traveling lamp") indicating that even the heavens are behaving strangely; the state of things is literally and figuratively dark. The old man notes that this is an unnatural state. Macbeth's crime has unleashed a supernatural chaos. The sky is dark when it should be light, and Duncan's horses went wild and ate each other. Scotland is in chaos.
The scene ends with Macduff and Ross discussing the upcoming coronation of Macbeth and Malcolm's and Donalbain's suspicious absence.
This scene is significant since it emphasizes the unnatural nature of Macbeth's malicious deed. It follows directly after the discovery of the king's slaying and the death of his guards soon after. Macbeth and his wife had plotted Duncan's assassination and, when he murdered his liege and cousin, he overturned the natural order and upset the balance in nature. The king's throne was supposed to fall to Duncan's direct heirs, Malcolm and Donalbain. In this regard, Malcolm had been named Prince of Cumberland by his now-deceased father, which meant that he was to become king after his father's natural death.
However, the king's death was unnatural for he had been slain in his bed - his demise was, therefore, untimely. Since suspicion now falls on Malcolm and his brother for having committed this most heinous crime, they have to escape to avoid persecution. This leaves the throne available to their uncle, Macbeth - which adds to the abnormality. Macbeth was to succeed only if Duncan left no direct heirs.
The scene depicts Ross speaking to an old man who has commented that he has never, in his seventy years, witnessed scenes in nature as dreadful and strange as the ones he has been seeing. It is terrifying. Ross states that heaven is expressing its consternation over man's bloody deeds which threatens everyone. He states that, according to the clock, it's supposed to be daylight but they are surrounded by darkness. This is an obvious reference to an eclipse, a common Shakespearian technique, to indicate a time of turmoil, disruption and disorder.
Because there has been a disruption in the natural order of things, it is as if nature, in its response, also acts in reverse. Ross surmises that it is either the presence of dark and evil forces that has usurped the day or it is that the light is too ashamed to appear because of the terrible deed that had been enacted (Duncan's murder). Day has literally become night.
The men also comment about strange and unnatural events, such as Duncan's horses going wild as if they were to attack humans and that they eat each other. The fact that a falcon was attacked by a mousing hawk is also mentioned - these were all omens of the horror that was to, and still is, to come.