Albert Barnes Commentary Isaiah 40:19

"The image, a workman hath cast [it], and the goldsmith overlayeth it with gold, and casteth [for it] silver chains." — Isaiah 40:19 (ASV)

The workman - The Hebrew word denotes a craftsman of any kind and is applied to one who engraved on wood or stone (Exodus 28:2); to a workman in iron, brass, stone, or wood (Exodus 35:35; Deuteronomy 27:15); or an artisan, or craftsman in general. It here refers clearly to a man who worked in the metals from which idols were commonly made. Those idols were sometimes made of wood, sometimes of clay, but more frequently, as they are at present in India, of metal. It undoubtedly became a regular trade or business to make idol-gods.

Melts - Casts or founds.

A graven image - (פסל pesel). This word commonly denotes an image carved or graven from wood (Exodus 20:4; Judges 17:3; Isaiah 44:15, 44:17), but it is also frequently applied to a molten image, or one that is cast from metals (Jeremiah 10:14; Jeremiah 51:17). It is used in this sense here, as there is an incongruity in the idea of casting or melting a graven image.

And the goldsmith spreads it over with gold - Idols were frequently overlaid with gold or silver. Those that were in the temples of the gods were probably commonly made in this way, and probably also those that were made for private use, as far as it could be afforded. The word here rendered ‘goldsmith,’ however, does not necessarily mean a worker in gold, but a smith in general, or a worker in any kind of metals.

And casts silver chains - For the idol. These were not to fasten it, but for the purpose of ornament. The general principle seems to have been to decorate their idols with what was regarded as the highest ornament among the people; and as chains were used in abundance as a part of their personal ornaments among Eastern peoples (see the notes at Isaiah 3:23), so they also used the same kind of ornaments for their idols. The idols of Hindus are now lavishly decorated in this manner.