What does Proverbs 19:28 mean?

Solomon (Proverbs 10:1) reflects on corrupt testimony. The idea of a "false witness" in Scripture mostly refers to legal settings: when someone lies in matters of judgment. The general idea applies to all cases of dishonesty, however. In his judicial experience Solomon probably encountered many false witnesses. This kind of evil person commits what modern courts call "perjury" and acts as if justice is a joke. This attitude is associated with those who eagerly wallow in sin (Proverbs 2:11–15; 6:12–15).

Lying under oath explicitly breaks the commandment given in Exodus 20:16: "You shall not bear false witness against your neighbor." False witnesses appeared at Jesus' trials and brought untrue accusations against Him (Matthew 26:59–61). Judas, who betrayed Jesus, thought it was good to do something similar by helping Jesus' enemies falsely accuse Him. He agreed to betray Christ for thirty pieces of silver. However, what he "devoured" so readily at first left a bitter taste. In the end, Judas threw the thirty pieces of silver into the temple, departed, and hanged himself (Matthew 27:3–6).