A Commentary, Critical, Practical, and Explanatory on the Old and New Testaments, by Robert Jamieson, A.R. Fausset and David Brown  at sacred-texts.com
job 28:1JOB'S SPEECH CONTINUED. (Job 28:1-28)
vein--a mine, from which it goes forth, Hebrew, "is dug."
place for gold--a place where gold may be found, which men refine. Not as English Version, "A place--where," (Mal 3:3). Contrasted with gold found in the bed and sand of rivers, which does not need refining; as the gold dug from a mine does. Golden ornaments have been found in Egypt, of the times of Joseph.
job 28:2brass--that is, copper; for brass is a mixed metal of copper and zinc, of modern invention. Iron is less easily discovered, and wrought, than copper; therefore copper was in common use long before iron. Copper-stone is called "cadmium" by PLINY [Natural History, 34:1; 36:21]. Iron is fitly said to be taken out of the "earth" (dust), for ore looks like mere earth.
job 28:3"Man makes an end of darkness," by exploring the darkest depths (with torches).
all perfection--rather, carries out his search to the utmost perfection; most thoroughly searches the stones of darkness and of the shadow of death (thickest gloom); that is, the stones, whatever they be, embedded in the darkest bowels of the earth [UMBREIT] (Job 26:10).
job 28:4Three hardships in mining: 1. "A stream (flood) breaks out at the side of the stranger"; namely, the miner, a strange newcomer into places heretofore unexplored; his surprise at the sudden stream breaking out beside him is expressed (English Version, "from the inhabitant"). 2. "Forgotten (unsupported) by the foot they hang," namely, by ropes, in descending. In the Hebrew, "Lo there" precedes this clause, graphically placing it as if before the eyes. "The waters" is inserted by English Version. "Are dried up," ought to be, "hang," "are suspended." English Version perhaps understood, waters of whose existence man was previously unconscious, and near which he never trod; and yet man's energy is such, that by pumps, &c., he soon causes them to "dry up and go away" [So HERDER]. 3. "Far away from men, they move with uncertain step"; they stagger; not "they are gone" [UMBREIT].
job 28:5Its fertile surface yields food; and yet "beneath it is turned up as it were with fire." So PLINY [Natural History, 33] observes on the ingratitude of man who repays the debt he owes the earth for food, by digging out its bowels. "Fire" was used in mining [UMBREIT]. English Version is simpler, which means precious stones which glow like fire; and so Job 28:6 follows naturally (Eze 28:14).
job 28:6Sapphires are found in alluvial soil near rocks and embedded in gneiss. The ancients distinguished two kinds: 1. The real, of transparent blue: 2. That improperly so called, opaque, with gold spots; that is, lapis lazuli. To the latter, looking like gold dust, UMBREIT refers "dust of gold." English Version better, "The stones of the earth are, &c., and the clods of it (Vulgate) are gold"; the parallel clauses are thus neater.
job 28:7fowl--rather, "ravenous bird," or "eagle," which is the most sharp-sighted of birds (Isa 46:11). A vulture will spy a carcass at an amazing distance. The miner penetrates the earth by a way unseen by birds of keenest sight.
job 28:8lion's whelps--literally, "the sons of pride," that is, the fiercest beasts.
passed--The Hebrew implies the proud gait of the lion. The miner ventures where not even the fierce lion dares to go in pursuit of his prey.
job 28:9rock--flint. He puts forth his hand to cleave the hardest rock.
by the roots--from their foundations, by undermining them.
job 28:10He cuts channels to drain off the waters, which hinder his mining; and when the waters are gone, he he is able to see the precious things in the earth.
job 28:11floods--"He restrains the streams from weeping"; a poetical expression for the trickling subterranean rills, which impede him; answering to the first clause of Job 28:10; so also the two latter clauses in each verse correspond.
job 28:12Can man discover the Divine Wisdom by which the world is governed, as he can the treasures hidden in the earth? Certainly not. Divine Wisdom is conceived as a person (Job 28:12-27) distinct from God (Job 28:23; also in Pro 8:23, Pro 8:27). The Almighty Word, Jesus Christ, we know now, is that Wisdom. The order of the world was originated and is maintained by the breathing forth (Spirit) of Wisdom, unfathomable and unpurchasable by man. In Job 28:28, the only aspect of it, which relates to, and may be understood by, man, is stated.
understanding--insight into the plan of the divine government.
job 28:13Man can fix no price upon it, as it is nowhere to be found in man's abode (Isa 38:11). Job implies both its valuable worth, and the impossibility of buying it at any price.
job 28:15Not the usual word for "gold"; from a Hebrew root, "to shut up" with care; that is, purest gold (Kg1 6:20, Margin).
weighed--The precious metals were weighed out before coining was known (Gen 23:16).
job 28:16gold of Ophir--the most precious (See on Job 22:24 and Psa 45:9).
onyx-- (Gen 2:12). More valued formerly than now. The term is Greek, meaning "thumb nail," from some resemblance in color. The Arabic denotes, of two colors, white preponderating.
job 28:17crystal--Or else glass, if then known, very costly. From a root, "to be transparent."
job 28:18Red coral (Eze 27:16).
pearls--literally, "what is frozen." Probably crystal; and Job 28:17 will then be glass.
rubies--UMBREIT translates "pearls" (see Lam 4:1; Pro 3:15). The Urim and Thummim, the means of consulting God by the twelve stones on the high priest's breastplate, "the stones of the sanctuary" (Lam 4:1), have their counterpart in this chapter; the precious stones symbolizing the "light" and "perfection" of the divine wisdom.
job 28:19Ethiopia--Cush in the Hebrew. Either Ethiopia, or the south of Arabia, near the Tigris.
job 28:20Job 28:12 repeated with great force.
job 28:21None can tell whence or where, seeing it, &c.
fowls--The gift of divination was assigned by the heathen especially to birds. Their rapid flight heavenwards and keen sight originated the superstition. Job may allude to it. Not even the boasted divination of birds has an insight into it (Ecc 10:20). But it may merely mean, as in Job 28:7, It escapes the eye of the most keen-sighted bird.
job 28:22That is, the abodes of destruction and of the dead. "Death" put for Sheol (Job 30:23; Job 26:6; Psa 9:13).
We have [only] heard--the report of her. We have not seen her. In the land of the living (Job 28:13) the workings of Wisdom are seen, though not herself. In the regions of the dead she is only heard of, her actings on nature not being seen (Ecc 9:10).
job 28:23God hath, and is Himself, wisdom.
job 28:24"Seeth (all that is) under," &c.
job 28:25God has adjusted the weight of the winds, so seemingly imponderable, lest, if too weighty, or too light, injury should be caused. He measureth out the waters, fixing their bounds, with wisdom as His counsellor (Pro 8:27-31; Isa 40:12).
job 28:26The decree regulating at what time and place, and in what quantity, the rain should fall.
a way--through the parted clouds (Job 38:25; Zac 10:1).
job 28:27declare--manifest her, namely, in His works (Psa 19:1-2). So the approval bestowed by the Creator on His works (Gen 1:10, Gen 1:31); compare the "rejoicing" of wisdom at the same (Pro 8:30; which UMBREIT translates; "I was the skilful artificer by His side").
prepared--not created, for wisdom is from everlasting (Pro 8:22-31); but "established" her as Governor of the world.
searched . . . out--examined her works to see whether she was adequate to the task of governing the world [MAURER].
job 28:28Rather, "But unto man," &c. My wisdom is that whereby all things are governed; Thy wisdom is in fearing God and shunning evil, and in feeling assured that My wisdom always acts aright, though thou dost not understand the principle which regulates it; for example, in afflicting the godly (Joh 7:17). The friends, therefore, as not comprehending the Divine Wisdom, should not infer Job's guilt from his sufferings. Here alone in Job the name of God, Adonai, occurs; "Lord" or "master," often applied to Messiah in Old Testament. Appropriately here, in speaking of the Word or Wisdom, by whom the world was made (Pro 8:22-31; Joh 1:3; Ecclesiasticus 24:1-34).