This verse completes the drinking warning begun at 31:4.
Quick answer
The reason kings must stay clear: drink makes rulers forget the law and bend the justice of the afflicted, the footnote reads literally "sons of affliction." The cost of a clouded throne lands on the people with the least.
Read the whole unit
The book's last chapter opens with a unique voice: the words of King Lemuel, "the utterance which his mother taught him." Lemuel appears nowhere else in Scripture, and the counsel he carries is the only teaching in Proverbs explicitly credited to a woman. Its structure is a queen mother's brief: the triple address of maternal urgency (v. 2), then three dangers ranked by what they cost a king: women who consume royal strength (v. 3), wine that clouds royal judgment (vv. 4–5, with a sharp aside on where strong drink might mercifully go instead, vv. 6–7), and finally the positive charge that everything was protecting: open your mouth for the speechless, judge righteously, plead the cause of the poor and needy (vv. 8–9). The logic runs on vocation. A king's strength, clarity, and voice are not his own; they are held in trust for people who have none of the three. The unit ends, and the acrostic begins, and the book closes with the counsel of a mother followed by the praise of a woman, wisdom's last two teachers both unexpected and both unforgettable.
What this verse contributes
This verse contributes the arithmetic that makes the previous verse urgent. A private man's drunkenness wrecks his own house; a ruler's drunkenness re-prices justice for everyone under him, and the first to pay are the afflicted, whose cases are marginal, whose advocates are few, and whose rights survive only where judgment stays sharp. "Forget the law" is the quiet catastrophe: not repealing justice, just not quite remembering it, case by case, until the vulnerable learn the courts are weather. The mother's counsel keeps circling one conviction: the powerless are the true measure of power used well, and vv. 8–9 will say it aloud.
Related: Proverbs 16:12 · Isaiah 28:7 · Proverbs 22:22–23
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.