Human nature and the ability to judge true character from a young age present a complex puzzle. The relationship between outward behavior, hidden motives, and a person's ultimate path in life is deeply intertwined. Early actions and youthful mischief [מצודת ציון, ביאור שטיינזלץ] often provide a window into a person's purity, showing whether they are free from wrongdoing, much like refined oil cleared of impurities [אבן עזרא, ביאור שטיינזלץ, מלבי״ם], and whether they are truly honest and far from crookedness [מלבי״ם].
The primary approach among commentators is that a young person's current behavior serves as a reliable indicator of their future. Because human personality rarely undergoes extreme transformations, early habits make a person easily recognized and understood [ביאור שטיינזלץ]. A wise observer watching a youth can often predict the direction they will take in adulthood, whether toward good or bad [עמנואל הרומי].
Looking deeper into human psychology, there is a fundamental difference between a single, isolated deed and consistent behaviors that stem from root character traits, such as pride, humility, or mercy. When a young person performs an action with an unclear motive, their true nature can be understood by examining their general habits. These foundational behaviors reveal whether a specific act was truly driven by a love for justice and honesty, or if it stemmed from improper motives [מלבי״ם].
Conversely, another perspective suggests that a young person's behavior can sometimes be deceiving, masking their true self [מצודת ציון, אבן עזרא]. This concealment can manifest in several ways. On a positive note, a youth might act completely out of step with their young age. While a foolish child is immediately obvious, a young person who performs good and honest deeds can mask their youth entirely. Observers might even forget their age, finding it hard to believe that a mere child is capable of such maturity [אבן עזרא].
On the negative side, early behavior can be a tool for hypocrisy and deception. Just like adults, young people are fully capable of hiding their true intentions. A person might act completely proper and good on the outside while harboring bad intentions within, especially since a young mind often serves its desires rather than controlling them [רלב״ג, מצודת דוד]. This reality provides insight into how God runs the world, particularly when it appears that a righteous person is suffering. Even if someone seems entirely innocent from their youth, their outward actions might not reflect a pure heart, and they may be hiding impure, selfish motives [אלשיך].
Finally, this masking of true character can result in a developmental surprise. While youth generally predicts adulthood, young people sometimes display the exact opposite of what they will eventually become. A diligent and intelligent youth might grow into a lesser adult, while a child who appears entirely foolish might develop into a clever and cunning grown person [עמנואל הרומי].