The proverb “not given is lost” vividly demonstrates that when property is entrusted to someone for use, its safekeeping and return remain the responsibility of the person who receives it.

Custody of Trust: The Inescapable Duty of Return

The proverb “not given is lost” vividly demonstrates that when property is entrusted to someone for use, its safekeeping and return remain the responsibility of the person who receives it. If the property is not returned to the owner intact and secure, the liability for its loss inevitably falls on the user. In other words, entrusted property never entirely becomes the property of the one who handles it, since holding it without the owner's consent is seen as a breach of trust.

This principle of responsibility is explained in detail in one of the sources that states:
“Here is what is yours” (Matthew 25:25).
Should a monetary or material deposit be returned after a matter that was initiated but did not come to fruition, or if funds were mistakenly received by someone in place of the designated person... Once it becomes clear to us that we are not the lawful owners, we must immediately return the property intact or, if physical return is impossible, compensate with money.
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The principle is further illustrated in the following excerpt:
“In little you have been faithful” (Matthew 25:23).
Sometimes the remaining money or materials might initially appear as merely surplus... Therefore, it must be returned to its owner, who decides whether to keep it or bestow it upon us as a reward.
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Thus, the proverb underscores that using someone else’s property entails an undeniable obligation to return it or compensate for it if its integrity is compromised. This teaching reminds us of the necessity to handle what is entrusted to us with the utmost responsibility.