This is an awesome question! I'm recovering from surgery, so I spent a little time researching this for you. Here's what I came up with.

So first, we need to break down a few things. Your question is an excellent one, but it comes with a lot of context. First, we know, rather specifically, that Macbeth was written sometime around 1606, maybe a little earlier. Cool. So what was going on around 1606? We're in England, so James I has been king for about 3 years, thusly unifying England and Scotland. England is a Protestant nation. More specifically, though, last year, on the 5th of November 1605, Guy Fawkes and a group of English Catholics tried to blow up Parliament and provided ample ammunition for anti-Catholic sentiments (and the backstory for a mid-quality movie starring Natalie Portman several years later).

It's also important to note that around this time period, the English government is working really hard to repress and censor any sort of Catholic books or materials, labeling them as "seditious material" and working to remove them from circulation. Peck writes that " The English government fully understood the power of the press in shaping public opinion, as it understood its own dependence upon the goodwill of its subject". However, what's important to keep in mind is that more than illegally published pamphlets or books, what has the potential to change the peoples' attitudes is public entertainment-- what's being shown at the playhouses.

So Shakespeare is in a dangerous and potentially politically advantageous position. He's writing a Scottish play for a Protestant Scottish King, but presenting a murderin', stabblin' type king who is encountering witches and ghosts and is clearly doing bad stuff in the name of getting power, which is,technically, a sin. So did James I like it? Hate it? Historians aren't really sure, but they all tend to agree that a modern reader can, at least, feel very strongly, the influence of James I on the text (Williams). Also important to quantify is Shakespeare's personal opinion on religion. Scholars have argued for years about whether or not Shakespeare was a secret Catholic, but for the purposes of this answer, I'm just going to stick to the content of his writing, rather than his personal life.

Let's break to talk about your original question, sin being a pre-peremptory basis for more sin as it relates to Macbeth. (I am going to take the liberty of slightly side-stepping your question about the soul, specifically, since that is an entirely different can of theological worms and this is getting way too long anyway). Disclaimer: I am NOT a theologian, so if there are any esteemed historians on this forum who can correct me, feel free. Basically in 1606, you're on one of two teams: Catholic (even though you're not supposed to be) or Protestant. The problem, really, is that religion at the time is so unbelievably political that it's a bit tangly.

The Protestants believed that if you're a human, sorry, thanks for playing, but you're inherently a sinner. Sin is just a part of the human condition, but all are saved through the sacrifice of Christ on the cross. Catholics, however, believe that there are sort of degrees to sin-- so you've got your little sins and big sins, but they all stem from the "original sin" of Adam and Eve. So they're...kind of exactly the same thing but also not at all. The Protestant brand of faith rejected the traditional Catholic models of reconciliation and forgiveness (because the Catholics figured out how to monetize it with indulgences), and instead created it as a more private encounter between you and God and sometimes the congretation, but there didn't need to be an "official" ceremony, unlike in the Catholic church.

However, to the best of my research/knowledge, both teams had, fundamentally, the same opinion: humans are inherently flawed, but if you try real hard and believe in yourself, you can live a good life, and through the grace of God, if you're sorry for the bad stuff you did, God will forgive you and you can continue trying to be a good person.

Back to your question. (I promise this is going somewhere). So you're living in England in 1606. Death is...basically everywhere. You've got plague, childbirth, generally crappy medical care, dirty water, ongoing wars...basically every time you stepped outside of your house, something could kill you. Religion is, to you and the rest of the country, a salve that makes you feel a little bit better about all that plague stuff. But since this is the Renaissance, all of the sudden, all of these new-fangled writers are coming in with new ideas about death, sin and redemption. What's a good, God-fearing countryman like you to do? Let's say you decide to get your mind off of it and go see a play. You go to see Macbeth.

So you're watching Macbeth, and it's the end of the show, and Macbeth is up there Tomorrow and Tomorrow and Tomorrowing, and you, middle-class merchant of 1606, is standing there thinking...what? In "Shakespeare's Treatment of Elizabethan Ideals on Life and Death", Loris Elaine Sebert writes " At this point in the play Macbeth begins to realize that his ambition is driving him deeper into sin than he at first thought it would. Moreover, in his new position as king, he finds that he has responsibilities which are not always pleasant nor easily dealt with". No shit. Macbeth is talking about death and sin, but in a way that transcends both the Catholic and Protestant experience, and kind of just...deals with it like a dude who is having a really bad day.

But you're at a play-- just like going to see The Avengers in 2017 isn't a spiritual experience, can we assume that playgoers of the time would have been looking for codified messages in shows? Probably not. In his review of "Shakespeare and Christian doctrine", Joseph G. Milunas writes that "Not all Shakespearean scholars and critics are agreed on the extent to which Christian doctrine permeates the plays of Shakespeare. Some are very skeptical of what they call the Christian approach to Shakespeare. In their view, Christianity and tragedy are incompatible. Furthermore, the interpretations proposed by many of the Christian interpreters hardly inspire confidence. Instead of illuminating the plays the Christian approach often distorts them".

However, Macbeth gets his comeuppance at the end, which is what you get for all that aforementioned murderin' and stabbin'. Sebert writes that "The inevitability of death was held up before the reader in all its horror as an end to a life of sin". (If you want to learn more about how this relates to Macbeth, check out Chapter 2 where she writes a crazy-good chapter on it. It's so good though, spend 10 minutes and read it).

So, basically, ALL of this to say that...maybe. The belief system of the time was an incredibly politicized and complicated situation that was further expanded by new ideas coming in from writers with new and readily available print materials. The Elizabethan (and on) ideals about forgiveness and sin are complex, but I think if you contextualize them within the world of 1606 as well as within Macbeth as a whole, you'll see that there are loads of places where you could argue your point is absolutely correct, and other places where you could easily refute it.

TLDR: Maybe(?) Aren't non-answers the best?

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