Practice yourself what you preach.

The maxim urges consistency between one’s words and one’s actions: moral instruction or advice carries weight only when the speaker embodies it. It targets hypocrisy—especially the tendency to demand discipline, virtue, or restraint from others while exempting oneself. In a Plautine context (Roman comedy), such a sentiment often functions as a pointed rebuke within dialogue, exposing a character’s pretensions and inviting the audience to laugh at the gap between public posturing and private behavior. More broadly, the line has endured as a compact ethical principle: credibility and authority are earned through example, not exhortation.