Amos 8:5
3 The women singing in the temple will wail in that day.” The Sovereign Lord is speaking. “There will be many corpses littered everywhere! Be quiet!” 4 Listen to this, you who trample the needy and do away with the destitute in the land. 5 You say, “When will the new moon festival be over, so we can sell grain? When will the Sabbath end, so we can open up the grain bins? We’re eager to sell less for a higher price, and to cheat the buyer with rigged scales! 6 We’re eager to trade silver for the poor, a pair of sandals for the needy. We want to mix in some chaff with the grain!” 7 The Lord confirms this oath by the arrogance of Jacob: “I swear I will never forget all you have done!
Proverbs 11:1
1 The Lord abhors dishonest scales, but an accurate weight is his delight. 2 After pride came, disgrace followed; but wisdom came with humility. 3 The integrity of the upright guides them, but the crookedness of the treacherous destroys them.
Notes and References
"... Adulteration of products was a problem even in ancient times as can be seen from Isaiah’s criticism (1:22) of the Israelites: 'Your silver has become dross, your wine diluted with water.' According to most commentaries, this is not a metaphor but refers to actual deceptive practices in ancient Judah and Jerusalem that angered the Lord. Merchants were prohibited from falsifying weights and measures by the Torah or even owning a dishonest weight (Leviticus 19:35-36; Deuteronomy 25:13-15). The prophet Amos (8:5) reproached the Jews for 'making the ephah (a dry measure) smaller and the shekel larger and falsifying the scales of deceit.' After all, 'Deceitful scales are an abomination of the Lord' (Proverbs 11:1). In fact, any deception or dishonest business practice is 'an abomination unto the Lord, your God' (Deuteronomy 25:16). To ensure honest weights and measures, the Talmud (T. Bava Bathra 88a) required merchants to wipe their weights once a week and clean their scales after every weighing. Market commissioners were appointed to ensure that businesses used honest weights and measures (T. Bava Bathra 89a). Vendors were prohibited from rapidly pouring liquids from great heights (T. Bava Bathra 89b), which was done by retailers to generate foam thereby ensuring that the customer would end up with less product ..."
Friedman, Hershey H. The Impact of Jewish Values on Marketing and Business Practices (pp. 74-80) Journal of Macromarketing, Vol. 21, 2001