From Deuteronomy 25:
13 Do not have two differing weights in your bag—one heavy, one light. 14 Do not have two differing measures in your house—one large, one small. 15 You must have accurate and honest weights and measures, so that you may live long in the land the Lord your God is giving you. 16 For the Lord your God detests anyone who does these things, anyone who deals dishonestly.
(I first learnt this when I read Guido Hülsmann’s book “The Ethics of Money Production“)