Yahweh requires justice and fairness when doing business. Dishonest people used heavier or lighter weights in their scales in order to gain more when buying or selling. (See: [[rc://en/ta/man/translate/figs-explicit]])
Merchants carried their weights in bags. Possible meanings are 1) Yahweh has determined how much every weight must weigh or 2) Yahweh is concerned with every weight that a merchant uses.