What does Proverbs 31:9 mean?

Lemuel's mother (Proverbs 31:1–2) urges her son not to be passive about those in need. Other lessons in the book of Proverbs indicate that righteous rulers care for the poor and weak (Proverbs 21:13; 29:7, 14). As a king, Lemuel is being taught to not merely tolerate those who are weak, but to lend his voice to the "mute" (Proverbs 31:8) and his defense to those who are defenseless.

Cruel rulers and political leaders often prey on those with less power. An example is what wicked King Ahab and Queen Jezebel did to Naboth (1 Kings 21). Ahab wanted Naboth's vineyard but Naboth refused to part with his familial land. So, Jezebel arranged for Naboth to be falsely accused; he was stoned to death because of the witnesses' false accusations. When Naboth was killed, Jezebel told Ahab to seize the vineyard, which he did. The whole evil episode angered the Lord, who commanded Elijah to confront Ahab with the message: "In the place where dogs licked up the blood of Naboth shall dogs lick your own blood" (1 Kings 21:19).

When Jesus returns to earth and establishes His kingdom, justice will be administered righteously. Isaiah 11:3–4 foretells that King Jesus "shall not judge by what his eyes see, or decide disputes by what his ears hear, but with righteousness he shall judge the poor, and decide with equity for the meek of the earth."