What changes after Macbeth announces that he has killed Duncan and Why?Compare how things were at the estart and end and also talk about changes in Macbeths reputation as well as other themes.
Macbeth returns to his "unsure" self when he bantered with his wife about killing the King to get to his goal and bring the witches' prophecy into fruition. He is unsure because he could not pray or say "Amen" to the prayer that he heard coming from the sons' room. He also heard a voice say, "Macbeth has murdered sleep" which makes him unsettled. In addition, the knocking of the door and the reports of the weird animal behavior and weather patterns add to the unrest.
This does not last long, though. Macbeth suddenly pours out all the "milk of human kindness" that his wife feared in him, and he plots the murders of his best friend (Banquo) and Banquo's son (Fleance), as well as the entire MacDuff family. Lady Macbeth, in turn, becomes withdrawn, won't be without a candle or some other light, begins sleepwalking, and eventually commits suicide to illustrate her guilt to the masses.