משלי, פרק י״ב, פסוק י״ט

The fundamental difference between truth and falsehood lies in the test of time. While truth possesses an internal stability that allows it to endure naturally, falsehood is inherently fragile, temporary, and entirely baseless [רש״י, ביאור שטיינזלץ, עמנואל הרומי]. Honest speech and truthful testimony establish a foundation that remains firm and lasts forever [אבן עזרא, רש״י, מצודת דוד, ביאור שטיינזלץ].

In sharp contrast, a lie cannot survive over time. The primary approach among commentators is that falsehood exists only for a brief, fleeting moment before it completely vanishes [רש״י, מצודת ציון, רלב״ג, ביאור שטיינזלץ]. Other perspectives connect the lifespan of a lie to the concept of rest or quiet. Some suggest that a lie will simply be silenced [אבן עזרא]. Another view proposes that a lie only survives until a person stops, rests, and takes a moment to think logically. The very second someone dedicates real thought to the matter, the deception is exposed [אלשיך]. A similar idea suggests that the short amount of time it takes for a person to rest from their daily work is all the time it takes for a liar to be removed from the world [אמרי דעת].

This principle plays out clearly in legal and practical settings, especially regarding testimony. A person who gives a truthful account can be questioned a hundred times, and every single time, their story will remain consistent and accurate. On the other hand, a false testimony only survives the exact moment it is spoken. During any further investigation, the false witness will inevitably change their story, adding or leaving out details, which ultimately exposes the lie [עמנואל הרומי, אלשיך, מצודת דוד].

Beyond legal matters, this rule applies to logic and philosophy. Basic logic dictates that a true concept will never change [רלב״ג]. When a person builds an argument on true foundations, the resulting conclusions will hold up forever. However, if someone bases their claims on false and misleading assumptions, their arguments will immediately collapse the moment a wise person examines them and spots the trick [עמנואל הרומי]. Ultimately, truth naturally grows stronger as time passes, whereas a lie has no legs to stand on, causing its brief existence to fade away rapidly [רש״י, אלשיך].