דברים, פרק כ״ה, פסוק י״ד

A strict standard of absolute honesty in business is required, demanding not just fair behavior in practice but the complete removal of any potential for cheating from the private space. The focus extends beyond the act of theft itself to the mere possession of tools designed to deceive others. Specifically, this involves tools used for measuring the volume of goods [ביאור שטיינזלץ]. The restriction against owning large and small variations does not forbid a person from keeping standard measuring containers of different sizes. Instead, it warns against keeping two different versions of the exact same unit of measurement—one larger than the standard and one smaller [רלב״ג, תורה תמימה]. The intent behind such deceitful tools is to buy goods from others using the oversized measure and sell them back using the undersized one, allowing the merchant to profit through trickery [רלב״ג, ביאור שטיינזלץ].

The fact that these items are forbidden even within the private home highlights that God hates not only the actual perversion of justice but also the mere possession of items prepared to commit an injustice. These tools must be entirely banished from the house so that God does not reject the inhabitants, allowing His blessing to rest upon their actions [ספורנו]. Even if a person has no intention of cheating, they are forbidden from keeping altered measures, as their very presence might tempt someone to act dishonestly [ביאור שטיינזלץ]. Furthermore, keeping a defective measure is prohibited even if it is intended strictly for private, internal use within the home. There is a constant danger that family members might mistakenly use it in business transactions, or that others might unwittingly stumble into using it [תורה תמימה, מלבי״ם]. Unlike stone weights, which a merchant typically carries in their pocket, volume measures are stored in the house, making the risk of an accidental mix-up significantly higher [מלבי״ם].

Because ordinary people find it difficult to detect manipulated volume measures—unlike price gouging, which is much easier to notice—society has a strict obligation to appoint special inspectors to verify the accuracy of all measures in the marketplace [תורה תמימה]. Beyond the immediate command, the restriction itself serves as both a promise and a warning for the future. The primary approach among commentators is that if a person keeps deceitful measures in their home, their ultimate punishment will be losing everything, leaving their house entirely emptied of its assets. In contrast, those who are careful to keep only whole, honest weights and measures will be rewarded with abundance and blessing in their home.