Amos 8:5

When will the new moon be gone? The new moon, the first of the month, was observed as a popular holiday (2 Kings 4:23; cf. 1 Samuel 20:5; 1 Samuel 20:24), and marked by religious services Isaiah 1:13-14; Hosea 2:11; and often in later writings: cf. Numbers 28:11-15). From the present passage, it is apparent that, like the sabbath, it was a day on which trade was suspended, and which accordingly was viewed by the grasping Israelitish merchants with impatience, on account of the interruption which it occasioned in their unjust practices.

making the ephah small&c. The ephahby which they sold was of short measure, while the shekel, by which the money to be paid by the purchaser was weighed, was unduly heavy. Dr Chaplin found in 1890, on the site of the ancient Samaria, a weight (now in the Ashmolean Museum, Oxford) inscribed (if של be rightly explained as an abbreviation for שלם) "a quarter of full weight." This weight weighs 39.2 grains, which would give a shekel of 156.8 (or rather more, if something be allowed for wearing). The weight of the so-called -light" shekel (the -heavy" shekel was twice as much) was probably 130 135 grains: whence W. R. Smith very ingeniously conjectured (P.E.F.Qu.St[191], 1894, p. 229) that the weight in question was a heavy quarter-shekel, of the kind alluded to here by Amos.

[191] .E.F.Qu.St.… Palestine Exploration Fund, Quarterly Statements.

falsifying the balances of deceit i.e. tampering with the balances by which the money received by them was weighed, and so gaining a third unjust advantage over the purchaser. See, in condemnation of such commercial dishonesty, Leviticus 19:35-36; Deuteronomy 25:13-15 ("Thou shalt not have in thy bag a weight and a weight,a great and a small. Thou shalt not have in thy house an ephah and an ephah,a great and a small," &c.); Proverbs 20:10 ("A weight and a weight, an ephah and an ephah, both of them alike are Jehovah's abomination"); Ezekiel 45:9-10. The ephah was probably equal to about eight gallons.