Some examples of personification in Macbeth include the lines "dark night strangles the travelling lamp" (Act 2, Scene 4) and "new sorrows / Strike heaven on the face" (Act 4, Scene 2). Shakespeare often uses personification, which is a literary device by which non-human ideas and objects are referred to as human.
It is essentially a type of metaphor, used to evoke the strong imagery that Macbeth is known for.
Another key example of personification in the play comes in Act 5, Scene 5, when Macbeth describes life as "but a walking shadow, a poor player." He says this despondently in response to news that the "trees" of Birnam Wood are marching on Dunsinane.