But he is in one mind - He is unchangeable. He has formed his plans, and no one can divert him from them. Of the truth of this sentiment there can be no dispute. The only difficulty in the case is to see why Job adverted to it here, and how it bears on the train of thought which he was pursuing. The idea seems to be, that God was now accomplishing his eternal purposes in respect to him; that he had formed a plan far back in eternal ages, and that that plan must be executed; that he was a Sovereign, and that however mysterious his plans might be, it was vain to contend with them, and that man ought to submit to their execution with patience and resignation. Job expected yet that God would come forth and vindicate him; but at present all that he could do was to submit. He did not pretend to understand the reason of the divine dispensations; he felt that he had no power to resist God. The language here is that of a man who is perplexed in regard to the divine dealings, but who feels that they are all in accordance with the unchangeable purpose of God.
And what his soul desireth, even that he doeth - He does what he pleases. None can resist or control him. It is vain, therefore, to contend against him. From this passage we see that the doctrine of divine sovereignty was understood at a very early age of the world, and entered undoubtedly into the religion of the patriarchs. It was then seen and felt that God was absolute; that he was not dependent on his creatures; that he acted according to a plan; that he was inflexible in regard to that plan, and that it was in vain to attempt to resist its execution. It is, when properly understood, a matter of unspeakable consolation that God has a plan - for who could honor a God who had "no" plan, but who did everything by hap-hazard? It is matter of rejoicing that he has "one" great purpose which extends through all ages, and which embraces all things - for then everything falls into its proper place, and has its appropriate bearing on other events. It is a matter of joy that God "does" execute all his purposes; for as they are all good and wise, it is "desirable" that they should be executed. It would be a calamity if a good plan were not executed. Why then should people complain at the purposes or the decrees of God?

But he is in one mind - The original is והוא באחד vehu beechad, and is literally, But he is in one: properly rendered by the Vulgate, Ipse enim solus est. But he is alone. And not badly rendered by Coverdale - It is he himself alone. He has no partner; his designs are his own, they are formed in his infinite wisdom, and none can turn his determinations aside. It is vain, therefore, for man to contend with his Maker. He designs my happiness, and you cannot prevent its accomplishment.

But he [is] in one [mind], and who can (h) turn him? and [what] his soul desireth, even [that] he doeth.
(h) Job confesses that at the present he did not feel God's favour and yet was assured that God had appointed him to a good end.

But he is in one mind,.... Either with respect to his commandments, every precept remains in full force, he never alters the thing that is gone out of his lips, or delivers out other commandments different from, or contrary to what he has given; and therefore Job thought it his duty to abide by them, and not decline from them; which is the sense of a Jewish commentator (c), connecting the words with the preceding: Or with respect to his dispensations towards Job in afflicting him; which he continued notwithstanding his innocence, because he is a sovereign Being, and does whatsoever he pleases; he is unchangeable in his purposes and decrees; he is not to be wrought upon by any means to alter his fixed course; he is not to be contradicted nor resisted; and this was the reason why he would not be found by him, though he sought him so earnestly and diligently, and why he would not hear him, and would not appear to try his cause, though he knew he was innocent, because he was determined to go on to afflict him; and he never changes his mind, or alters his counsels, on any account whatever. The Vulgate Latin version renders it, "for he is alone": and so the Targum,
"if he is alone, or the only one;''
there is none with him to advise him, for "with whom took he counsel?" or to persuade him to be of another mind, and take contrary measures, who might be applied to, to use their interest with him to act it, a different manner; but he is alone, there are none with him that have any influence upon him, and can prevail with him to do otherwise than he does; some translate the words, "if he acts against one" (d); against a man in a hostile way, if he sets his face against him, and comes upon him as an enemy; and so Mr. Broughton, "yet when he is against me, who can stay him?" notwithstanding my innocence and integrity, though I keep his ways, and do not go back from his commandments. Some think there is a redundancy of a letter, which we translate "in", and then the words wilt be read thus: "but he is one"; the one only living and true God; this is the voice of reason and revelation, "hear, O Israel, the Lord thy God is one Lord", Deuteronomy 6:4; for though there are three Persons in the Godhead, Father, Son, and Holy Ghost, "these three are one God", 1-John 5:7; and so the words are expressive of the unity of the Divine Being; but this seems not to be Job's sense: Aben Ezra says, the truth is, that the letter is not added, is no redundancy, and should be read "he is in one"; but, says he, I cannot explain it, there is a great mystery in it: what the Jew understood not may be more clear and plain to us Christians, who are taught the mystery of the indwelling of the divine Persons in each other, the Father is in the Son, and the Son is in the Father, as they are divine Persons; though in what manner they are we are not able to explain; besides, God was in Christ, as Mediator, reconciling the world, choosing his people in him, and blessing them with all spiritual blessings in him; though the true sense seems to, be what is before given, agreeably to our version, that God is in one mind, purpose, and design; that his decrees are unchangeable and invariable; that he always acts according to them, and never alters them:
and who can turn him? turn his mind, or cause him to change his counsel, and alter his purposes; or turn his hand, or stop and stay it from the execution of them; it is not to be done by force and power, there is no power equal to his, and much less superior to his; which must be the case, if any could turn him: and though he may be turned by the prayers of his people, and by the repentance of men, so as to repent himself, and not do what he has threatened to do; yet this is no change of his mind and counsels, only an alteration in the course of his providence, or a change of his outward dealings with men, according to his unchangeable will; see Isaiah 14:27;
and what his soul desireth, even that he doth: that is, what he himself desireth earnestly and vehemently; he has done all things in creation according to the good pleasure of his will; and he does all things in providence according to the counsel of it, and as seems best in his sight; and so he does all things in grace, chooses whom he will, predestinates to the adoption of children according to the good pleasure of his will: redeems whom he pleases, and calls by his grace, and brings to glory whomsoever he will be gracious to; see Psalm 115:3.
(c) Sophorno. (d) "sed si ipse contra unum agit", Junius & Tremellius; so Piscator, Cocceius.

As Job does not once question but that his trials are from the hand of God, and that there is no such thing as chance, how does he account for them? The principle on which he views them is, that the hope and reward of the faithful servants of God are only laid up in another life; and he maintains that it is plain to all, that the wicked are not treated according to their deserts in this life, but often directly the reverse. But though the obtaining of mercy, the first-fruits of the Spirit of grace, pledges a God, who will certainly finish the work which he has began; yet the afflicted believer is not to conclude that all prayer and entreaty will be in vain, and that he should sink into despair, and faint when he is reproved of Him. He cannot tell but the intention of God in afflicting him may be to produce penitence and prayer in his heart. May we learn to obey and trust the Lord, even in tribulation; to live or die as he pleases: we know not for what good ends our lives may be shortened or prolonged.

in one mind--notwithstanding my innocence, He is unaltered in His purpose of proving me guilty (Job 9:12).
soul--His will (Psalm 115:3). God's sovereignty. He has one great purpose; nothing is haphazard; everything has its proper place with a view to His purpose.