And I will turn my hand upon thee This is an alleviation of the former threatening; for though he still proceeds with what he had begun to state about his severity, he at the same time declares that, amidst those calamities which were to be inflicted, the Church would be preserved. But the principal design was to comfort believers, that they might not suppose the Church to be utterly ruined, though God treated them more roughly than before. The Spirit of God, by the Prophets, continually warns the children of God, who always tremble at his word, not to be overwhelmed and lose heart on account of terrors and threatening; for the more daringly that wicked men practice licentiousness and scoff at all threatening the more do those who are affected by a sincere fear of God tremble at them. Besides, the turning of the hands of God denotes generally a token of his presence, as if he should say, I will display my hand. This he is wont to do in two ways, either by chastising the wicked, or by delivering believers from their distresses. Since, therefore, it is evident from the context that God purposes, by applying consolation, to mitigate the severity of punishment, the turning of the hands must here be viewed as referring to the restoration of the Church; for although he declared in general terms that all were his enemies, he now modifies or limits that statement by addressing Jerusalem or Zion by name. When he adds, I will purge away thy dross, though he points out the fruit of correction, that believers may not be immoderately grieved or distressed on account of it, yet we learn from this expression that the purification of the Church is God's own work. For this purpose he always lifts up his hand to punish transgressions, that he may bring back wanderers into the road; but rods would be of no avail, if he did not make them useful by touching their hearts inwardly. And, indeed, since he points out here a special favor which he bestows on his elect, it follows from this that repentance is a true and peculiar work of the Holy Spirit; for otherwise the sinner, instead of profiting in the smallest degree, would be more and more hardened by chastisements. The pure purging, so that no dross remains, must not, however, be understood as if God ever cleansed his Church entirely in this world from every stain, but must be regarded as spoken after the manner of men; as if he said that the condition of his Church will be such that her holiness will shine like pure silver. These words, therefore, indicate real purity, for the Jews had formerly been too well satisfied with their filthiness. This is a highly appropriate comparison, by which the Prophet declares, that though the Church was at that time polluted by many defilements, still some remnant would be left, which, after the removal of the pollution, would regain its brightness. In this manner he also connects both clauses; for when he formerly spoke of their crimes, he said that their silver had become dross. (Isaiah 1:22.)

And I will turn my hand upon thee - This expression is capable of two significations. The hand may be stretched out for two purposes, either to inflict punishment, or to afford help and protection. The phrase here refers evidently to the latter, to the act of redeeming and restoring his people, Isaiah 1:26-27. The idea may be thus expressed: 'I will stretch out my hand to punish my enemies Isaiah 1:24, and will turn my hand upon thee for protection, and recovery.'
Purge away - This refers to the process of smelting, or purifying metals in the fire. It means, I will remove all the dross which has accumulated Isaiah 1:22, and will make the silver pure. This was commonly done by fire; and the idea is, that he would render his own people pure by those judgments which would destroy his enemies who were intermingled with them.
Purely - The original word here - כבר kabor - has been commonly understood to mean, according to purity; that is, effectually or entirely pure. Thus it is translated by the Septuagint, and by the Latin Vulgate. But by the Chaldee it is translated, 'I will purify thee as with the herb borith.' The word may mean lye, alkali, or potash, Job 9:30; and it may mean also borax - a substance formed of alkali and boracic acid, much used in purifying metals. The essential idea is, I will make you effectually, or entirely pure.
Thy tin - Tin is with us a well-known white metal. But the word used here does not mean tin. It denotes the stannum of the ancients; a metal formed of lead mixed with silver ore. Here it means, I will take away all the impure metal mixed with thee; varying the idea but little from the former part of the verse.

I will turn my hand upon thee - So the common version; and this seems to be a metaphor taken from the custom of those who, when the metal is melted, strike off the scoriae with their hand previously to its being poured out into the mould. I have seen this done with the naked hand, and no injury whatever sustained.
Purge away thy dross "In the furnace" - The text has כבר cabbor, which some render "as with soap;" as if it were the same with כברית keborith; so Kimchi; but soap can have nothing to do with the purifying of metals. Others, "according to purity," or "purely," as our version. Le Clerc conjectured that the true reading is ככור kechur, "as in the furnace;" see Ezekiel 22:18, Ezekiel 22:20. Dr. Durell proposes only a transposition of letters בכר to the same sense; and so likewise Archbishop Secker. That this is the true reading is highly probable.

And I will turn my hand upon thee, and thoroughly purge away thy dross, (k) and take away all thy tin:
(k) Lest the faithful among them should be overcome with his threatening he adds this consolation.

And I will turn my hand upon thee,.... The remnant, according to the election of grace, left in Jerusalem, Isaiah 1:9 meaning not his afflicting hand, no, not even as a fatherly chastisement; though the Lord sometimes, by such means, purges away the iniquity of his people, as follows; see Isaiah 27:9 much less his hand of wrath and vengeance, the lighting down of his arm, with the indignation of his anger; but his hand of efficacious grace in conversion, with which he plucks sinners as brands out of the burning; delivers them from the power of Satan; turns their hearts to himself; opens them, to attend unto and understand divine things; breaks them in pieces with the hammer of his word; works grace in them, and carries on the good work in their souls: all which is owing to his mighty hand of grace upon them, and to the exertions of the exceeding greatness of his power towards them. This was accomplished in part in the conversion of a large number of the Jews on the day of Pentecost, and afterwards; and will be more fully accomplished in the latter day, when that people shall turn to the Lord, in consequence of his hand of powerful grace being turned on them. The phrase is used of the display of divine grace and mercy, in Zac 13:7.
and purely purge away thy dross; which the Targum rightly interprets of "ungodliness" or wickedness; it means the sins of converted ones, which, at conversion, they are purely purged from; not that sin, as to the being of it, is removed from them; that dwells in them, abides with them; and, like dross, is a heavy burden, a dead weight upon them, and will be while they are in this tabernacle, and makes them groan, being burdened; so far from it, that in their view it rather increases; they see the plague of their own hearts; and such innumerable swarms of corruption they never saw before; sin revives, and they die; but in conversion grace superabounds it, deluges over it, keeps down the force and power of it, so that it has not the dominion; the old man is put off concerning the former conversation, which ceases to be a series, a course of sinning: besides, through the sprinkling of the blood of Christ, which cleanseth from all the dross and filth of sin, the guilt is removed from the conscience, and perfect peace and full pardon take place; all iniquity is caused to pass from them, and they are clothed with change of raiment, the righteousness of Christ, by which they are justified from all things, and are pure, spotless, and without fault before the throne:
and take away all thy tin. The Targum also interprets this of iniquity, rendering it, "I will take away all thy sin"; but it is better to understand it of self-righteousness; which, as tin is of more worth than dross, and looks like silver; so this has the appearance of some good in it, and was what the Jews were fond of, trusted in, and depended on, and which they followed after, and endeavoured to establish and hold fast; but this in conversion is all taken away: the Lord, by his Spirit; convinces of the weakness and insufficiency of it, to justify in his sight; shows that it is not a righteousness, and will be of no service in that respect; yea, takes away these filthy rags, and clothes with the righteousness of Christ; causes the soul to drop and renounce its own righteousness, and put on that; and not only to renounce works before conversion, but all after it, as a profession of religion, subjection to Gospel ordinances, and all works, though done in faith, and in a right manner; a glaring instance we have of all this in one of that little remnant, the Apostle Paul, Philippians 3:6. Moreover, by "dross" and "tin", or "tins", in the plural number, may be meant persons; wicked and profane men, by the former, who should be put away like dross, Psalm 119:119 and self righteous persons, by the latter; who shine like silver, make a show of religion, appear outwardly righteous; but these, as well as the other, should be separated from the people of God, when the precious and the vile should be distinguished.

turn . . . hand--not in wrath, but in grace (Zac 13:7), "upon thee," as Isaiah 1:26-27 show; contrasted with the enemies, of whom He will avenge Himself (Isaiah 1:24).
purely--literally, "as alkali purifies."
thy dross--not thy sins, but the sinful persons (Jeremiah 6:29); "enemies" (Isaiah 1:24); degenerate princes (see on Isaiah 1:22), intermingled with the elect "remnant" of grace.
tin--Hebrew, bedil, here the alloy of lead, tin, &c., separated by smelting from the silver. The pious Bishop Bedell took his motto from this.

Isaiah 1:25 states clearly in what the revenge consisted with which Jehovah was inwardly burdened (innakmah, a cohortative with the ah, indicating internal oppression): "And I will bring my hand over thee, and will smelt out thy dross as with alkali, and will clear away all thy lead." As long as God leaves a person's actions or sufferings alone, His hand, i.e., His acting, is at rest. Bringing the hand over a person signifies a movement of the hand, which has been hitherto at rest, either for the purpose of inflicting judicial punishment upon the person named (Amos 1:8; Jeremiah 6:9; Ezekiel 38:12; Psalm 81:15), or else, though this is seldom the case, for the purpose of saving him (Zac 13:7). The reference here is to the divine treatment of Jerusalem, in which punishment and salvation were combined - punishment as the means, salvation as the end. The interposition of Jehovah was, as it were, a smelting, which would sweep away, not indeed Jerusalem itself, but the ungodly in Jerusalem. They are compared to dross, or (as the verb seems to imply) to ore mixed with dross, and, inasmuch as lead is thrown off in the smelting of silver, to such ingredients of lead as Jehovah would speedily and thoroughly remove, "like alkali," i.e., "as if with alkali" (Cabbor, Comparatio decurtata, for C'babbor: for this mode of dropping Beth after Caph, compare Isaiah 9:3; Leviticus 22:13, and many other passages). By bedilim (from bâdal, to separate) we are to understand the several pieces of stannum or lead
(Note: Plumbum nigrum, says Pliny, n. n. xxiv. 16, is sometimes found alone, and sometimes mixed with silver: ejus qui primus fluic in fornacibus liquor, stannum appellatur. The reference here is to the lead separated from the ore in the process of obtaining pure silver. In the form of powder this dross is called bedil, and the pieces bedilim; whereas ophereth is the name of solid lead, obtained by simply melting down from ore which does not contain silver. The fact that bedil is also apparently used as a name for tin, may be explained in the same way as the homonymy of iron and basalt (Com. on Job 28:2), and of the oak and terebinth. The two metals are called by the same name on account of their having a certain outward resemblance, viz., in softness, pliability, colour, and specific gravity.)
in which the silver is contained, and which are separated by smelting, all the baser metals being distinguished from the purer kinds by the fact that they are combustible (i.e., can be oxidized). Both bor, or potash (an alkali obtained from land-plants), and nether, natron (i.e., soda, or natron obtained from the ashes of marine plants, which is also met with in many mineral waters), have been employed from the very earliest times to accelerate the process of smelting, for the purpose of separating a metal from its ore.

And purge - I will purge out of thee, those wicked men that are incorrigible, and for those of you that are curable, I will by my word, and by the furnace of affliction, purge out all that corruption that yet remains in you.