Jeremiah concludes his subject by saying, -- that if the Jews had been cast a hundred times into the furnace, they would not be improved, as they would never become softened on account of their hopeless obstinacy. He uses the word silver, by way of concession; for they were not worthy of that name, and we have already seen that there was nothing soft or tender in them. But the prophets often conceded some things to hypocrites; yet not without some appearance of a taunt, as the case seems to be here. The Jews wished to be regarded as silver, and to appear as such: "Let them then be silver, "that is, "Let them claim the name, by boasting themselves as the holy seed of Abraham; but they are a reprobate silver;" according to what we say, Faux or faux argent; which yet is neither silver nor gold; but the words are used not in their strict meaning, and we afterwards shew that what we have so called is not silver. Even so does the Prophet say, "They are silver in their own esteem, and take pride in the title: but they are a reprobate silver." How so? For Jehovah has rejected them He shews that it belongs to God to pronounce sentence on men, and that they gain nothing by their vain flatteries, and by securing some esteem in the world: for God alone is the true judge. The Prophet then shews that the Jews were a reprobate silver, in order that they might know that they in vain gloried, while they boasted themselves to be God's people and heritage. Now follows --

Reprobate - See the margin; not really silver, but the dross.
The Lord hath rejected them - This then is the end. The smelter is God's prophet: the bellows the breath of inspiration: the flux his earnestness in preaching. But in vain does the fervour of prophecy essay to melt the hearts of the people. They are so utterly corrupt, that no particle even of pure metal can be found in them. All the refiner's art is in vain. They have rejected all God's gifts and motives for their repentance, and therefore Yahweh has rejected them as an alloy too utterly adulterate to repay the refiner's toil.

Reprobate silver shall men call them,.... Or, "call ye them" (i), as the Targum; so the Septuagint, Vulgate Latin, and Arabic versions; by whom are meant the Jews, who thought themselves of some account, as silver; being the seed of Abraham, and having the law, the covenant and promises, and service of God; when those that tried them, as the prophets, found them to be nothing but dross; and therefore, if they must be called silver, they could call them no other than reprobate silver; or what is of no account and value; and which is confirmed by the following reason, which contains the judgment and conduct of him that cannot err:
for the Lord hath rejected them; from being his people; and therefore cast them out of their own land, and caused them to go into captivity.
(i) , "vocate eos": V. L. Pagninus.

Reprobate--silver so full of alloy as to be utterly worthless (Isaiah 1:22). The Jews were fit only for rejection.
The prophet stood at the gate of the temple in order that the multitudes from the country might hear him. His life was threatened, it appears from Jeremiah 26:1-9, for this prophecy, denouncing the fate of Shiloh as about to befall the temple at Jerusalem. The prophecy given in detail here is summarily referred to there. After Josiah's death the nation relapsed into idolatry through Jehoiakim's bad influence; the worship of Jehovah was, however, combined with it (Jeremiah 7:4, Jeremiah 7:10).

The final statement of the case: They call them (the whole people) rejected silver, i.e., they are recognised as such; for Jahveh has rejected them, has given over trying to make anything of them.

Refuse - Such as will be rejected in payments.