This quote essentially emphasizes the moral dilemma of choosing between two wrongs. The first part,”It is indeed great sin to swear unto a sin,” suggests that making a promise or commitment to do something immoral or sinful is in itself a grave error. Though,the second part,”But greater sin to keep a sinful oath,” posits that actually following through on such an immoral commitment is even worse.

The quote highlights the complexity of morality and ethics. It raises questions about whether it’s better to break a promise (which is generally considered unethical) if that promise involves doing something morally wrong. It also underscores the importance of discernment and judgment when making commitments – we should avoid committing ourselves to actions that may lead us down an unethical path.

In today’s world, this idea could be applied in numerous ways. For instance, consider someone who promises their friend they’ll lie for them if necessary but later finds themselves uncomfortable with this pledge when presented with the reality of it. According to Shakespeare’s wisdom here, it would be more sinful for them to keep this dishonest oath than breaking their word.

In terms of personal development, one might interpret this quote as an encouragement for introspection and moral courage – having the strength not only to recognize when you’ve made an improper commitment but also taking steps rectify it even if means breaking your word initially given.

Another viewpoint could be in professional contexts where people often face ethical dilemmas like being asked by superiors or colleagues to engage in activities they consider unethical such as lying or cheating clients etc., Here too Shakespeare’s wisdom can guide individuals; rather than going along with such requests (even though they have sworn allegiance/loyalty towards their company/colleague), they should stand up against what’s morally incorrect – thus emphasizing integrity over blind loyalty.