The second line is genuinely disputed in Hebrew, and the NKJV footnotes the difficulty itself. It is also one of the most quoted verses in the book.
Quick answer
A good life feeds other people. The famous second line is harder to translate than its popular use suggests, and the entry below says why.
Read both lines
The first line is clear and generous. "Tree of life" is the book's image for something that gives sustenance over time, used already of wisdom at 3:18, and here it describes what a righteous life produces: fruit other people can eat. That is the verse's governing picture, and the second line should be read as its completion rather than as a separate topic. Whatever precisely the second line says, it says that this kind of life has an effect on other lives, and that the effect is what wisdom looks like.
Why translations differ
The Hebrew verb is laqach, which ordinarily means to take, and the NKJV footnotes it here as "Lit. takes, in the sense of brings," pointing the reader to 1 Samuel 16:11, where the same verb means "send and bring him." The object is nephashot, lives or souls. So the line reads, literally, something like "he who takes lives is wise," and translators have to decide what taking lives means in a verse about fruit. Renderings include "wins souls," "takes souls," "captivates people," and "the wise one draws people to himself." A few readers, taking "takes lives" in its harsher sense, have proposed the opposite meaning entirely, though that fits the first line poorly. This is a case for the third certainty register: the expression is genuinely debated, and the honest report is that the verse says a righteous life gathers people, without specifying the mechanism.
What it does not mean
Read in English, "he who wins souls is wise" has become a slogan for evangelism, and it is worth being clear about what the verse can and cannot carry. Proverbs is not talking about conversion; the concept is not in view in this book, and the phrase in Hebrew is not a technical term for it. That does not make the popular application wrong as a sentiment, since a life that draws people is in fact what the verse describes, but the verse should not be used as a proof text for a program, or as pressure on a believer who is told that soul-winning is the measure of their wisdom. The first line governs: this is about a life that bears fruit others can eat.
Related: Proverbs 3:18 · Proverbs 11:18 · 1 Samuel 16:11
New King James Version®, Copyright © 1982, Thomas Nelson. All rights reserved. Full copyright information. Scripture provided by API.Bible.
Go Deeper
If this verse has been used to put weight on you that it was never carrying, ask about it directly.