In Macbeth how does Shakespeare demonstrate how easily evil can destroy the human soul?What is shakespeare's interpretation of evil and what does a human soul mean?
Concerning your question about Shakespeare's Macbeth, I will play the devil's advocate a bit.
I don't know what a human "soul" is, as it is used in this prompt. It seems to me that the term is something that is useful in a work of art like this play, perhaps, but not useful in criticism or discussion of a work of art: it's too imprecise. Strictly speaking, the soul is a second part of a human being that is saved or lost, according to Christian beliefs, which mirror the Greek belief in the dichotomy (different parts) of a human being. If you use the term this way, then your question just refers to evil causing Macbeth to be damned. If this is the case, then the answer is quite simple, perhaps: Macbeth does evil acts, is or becomes evil, then faces eternal damnation, according to Christian beliefs.
But I think the prompt uses soul in a different manner, which is difficult to define. I think it refers to soul in that broad, perhaps undefinable, way used by different people to mean whatever they think it means. The word tends to refer to some deeper part of a human being, some essential part, what makes us tick, so to speak. But the term is so vague that it probably has no place in criticism or literary analysis.
Even if one does use the term in this manner and answers the prompt, however, there is still a problem. Isn't Macbeth evil already? Doesn't the evil come from within Macbeth himself? The prompt seems to identify evil as a separate entity, as if evil somehow influences Macbeth and makes him kill Duncan.
In other words, if Macbeth is evil already, and if the evil comes from within Macbeth, then evil is what Macbeth is and it doesn't destroy anything. Macbeth is evil, and he is ambitious. He kills or orders the killings of numerous people due to his ambition. Evil is not something that destroys Macbeth. Evil is what Macbeth is or becomes.
The prompt, then, has two problems: the way it uses "soul" and the way it uses "evil." I don't know what "soul" is, but Macbeth is evil, most likely even before he hears the witches' predictions, and he is ambitious. And his ambition makes him commit evil acts.