Ecclesiastes 7:17, "Don’t be too wicked, neither be foolish. Why should you die before your time?" is a piece of wisdom from a book that is often exploring the complexities and ironies of life. Let's break down the meaning:

"Don't be too wicked...": This is a call against excessive sin and immorality. It suggests that indulging in wickedness has consequences that can lead to an early death. The idea is that a life of crime, violence, or recklessness often results in a premature end, whether through punishment, retaliation, or the inherent dangers of that lifestyle.
"...neither be foolish.": This is more nuanced than just "don't be stupid." In this context, "foolish" likely refers to a kind of self-destructive naivety or lack of wisdom. It suggests avoiding actions or decisions that, through ignorance or lack of foresight, will lead to negative consequences. This might include reckless behavior, neglecting one's health, or making poor decisions that put oneself in harm's way.
"Why should you die before your time?": This is the key question that encapsulates the point. It suggests that both excessive wickedness and foolishness can shorten one's lifespan. The verse implies that there is a natural lifespan, and that one should strive to live it out. It is a call to live wisely, avoiding behaviors that could bring about an untimely death.

In essence, the verse is a call to moderation and prudence. It's not necessarily about moral perfection, but about using common sense and avoiding extremes that could lead to an early demise. It acknowledges that actions have consequences, and that living a balanced life is more likely to lead to a longer, more fulfilling one. It highlights both moral and practical dimensions of leading a good life. It acknowledges that extreme wickedness can invite trouble, while extreme foolishness makes you vulnerable to it.