John Calvin Commentary Exodus 20:15

"Thou shalt not steal." — Exodus 20:15 (ASV)

Since charity is the end of the Law, we must seek the definition of theft from that principle. This, then, is the rule of charity: that everyone’s rights should be safely preserved, and that no one should do to another what he would not want done to himself.

It follows, therefore, that not only are those thieves who secretly steal the property of others, but also those who seek gain from the loss of others, accumulate wealth by unlawful practices, and are more devoted to their private advantage than to equity. Thus, plunder is included under the category of theft, since there is no difference between robbing one's neighbor by fraud or by force.

But, so that God may more effectively restrain His people from all fraudulent injustice, He uses the word 'theft,' which all naturally abhor as disgraceful. For we know under how many disguises people bury their misdeeds; and not only so, but also how they convert them into praise by false pretexts.

Craft and low cunning are called prudence; and he is spoken of as provident and circumspect who cleverly overreaches others, who deceives the simple, and insidiously oppresses the poor. Since, therefore, the world boasts of vices as if they were virtues, and thus all freely excuse themselves in sin, God wipes away all this veneer when He pronounces all unjust means of gain to be so many thefts. Nor should we be surprised that this decision is given by the divine tribunal, when philosophers deliver nearly the same doctrine.

We must also bear in mind that an affirmative precept, as it is called, is connected with the prohibition. This is because, even if we abstain from all wrongdoing, we do not thereby satisfy God. He has laid humanity under mutual obligation to each other, so that they should seek to benefit, care for, and aid their neighbors.

Therefore, He undoubtedly teaches and urges liberality and kindness, and the other duties by which human society is maintained. And for this reason, so that we may not be condemned as thieves by God, we must endeavor, as far as possible, that everyone should safely keep what he possesses, and that our neighbor’s advantage should be promoted no less than our own.