He causeth it to come - That is, the rain, or the storm. It is entirely under the hand of God, like the lightning Job 36:30, and designed to accomplish his purposes of mercy and of justice.
Whether for correction - Margin, as in Hebrew "a rod." The rod is often used as an emblem of punishment. The idea is, that God, when he pleases, can send the rain upon the earth for the purpose of executing punishment. So he did on the old world Genesis 7:11-12, and so the overflowing flood is often now sent to sweep away the works of man, to lay waste his fields, and to cut off the wicked.
Or for his land - When necessary to render the land productive. He waters it by timely rains. It is called "his land," meaning that the earth belongs to the Lord, and that he cultivates it as his own; Psalm 24:1.
Or for mercy - In kindness and benignity to the world. But for this, the earth would become baked and parched, and all vegetation would expire. The idea is, that the rains are entirely under the control of God, and that he can make use of them to accomplish his various purposes - to execute his judgments, or to express his benignity and love. These various uses to which the lightning, the storm, and the rain could be made subservient under the divine direction. seem to have been one of the main ideas in the mind of Elihu, showing the supremacy and the majesty of God.

He causeth it to come - The Vulgate translates the text thus: Sive in una tribu, sine in terra sua, sive in quocunque loco misericordiae suae eas jusserit inveniri. "Whether in one tribe, or whether in his own land, or in whatsoever place of his mercy he has commanded them to come." In the preceding verse it is said that God conducts the clouds according to the orders of his counsels, whithersoever he pleases: and here it is added that, when he designs to heap favors upon any land, he commands the clouds to go thither, and pour out on it their fertilizing showers. See Calmet. The Vulgate certainly gives a good sense, and our common version is also clear and intelligble; but there are doubts whether the Hebrew will bear this meaning. Here it is stated that God sends the rain either for correction, לשבט leshebet, which signifies rod, staff, tribe, and is here taken as the symbol of correction, he sends rain sometimes as a judgment, inundating certain lands, and sweeping away their produce by irresistible floods: or for his land, לארצו leartso, his own land, Palestine, the place of his favored people: or for mercy, לחסד lechesed; when a particular district has been devoured by locusts, or cursed with drought, God, in his mercy, sends fertilizing rains to such places to restore the ears which the caterpillars have eaten, and to make the desert blossom like the garden of the Lord. Some think that Job refers to the curse brought upon the old world by the waters of the deluge. Now although God has promised that there shall no more be a flood of waters to destroy the whole earth; yet we know he can, very consistently with his promise, inundate any particular district; or, by a superabundance of rain, render the toil of the husbandman in any place vain. Therefore, still his rain may come for judgment, for mercy, or for the especial help of his people or Church.

He causeth it to come, whether for (k) correction, or for his land, or for mercy.
(k) Rain, cold, heat, tempests and such like are sent from God, either to punish man, or to profit the earth, or to declare his favour toward man, as in (Job 36:31).

He causeth it to come,.... The cloud, and rain by it;
whether for correction; for the reproof and chastisement of men for their sins, by suffering such quantities to fall as wash away, or corrupt and destroy, the fruits of the earth: or "for a tribe" (t), as the word sometimes signifies; the rain is sent, and comes only to a particular part or spot of ground, to one city and not to another, Amos 4:7;
or for his land; some particular land he has a favour for, as the land of Canaan he cared for from one end of the year to another, and therefore sent on it rain in due season, though as yet it did not appear to be the object of his peculiar regard; or for the whole earth, which is his; and wherever rain comes seasonably and in proper quantity, it is for the benefit of it; though some think the land which no man has a property in but the Lord is meant, even the wilderness where no man is, Job 38:26;
or for mercy; to some particular spot, and to some particular persons; and indeed it is a kindness and benefit both to good and bad men; hereby the earth is watered and made fertile and fruitful, to bring forth seed to the sower and bread to the eater, see Matthew 5:45; the word of God is for the correction of some, and for the comfort of others, 2-Timothy 3:16; yea, the savour of death unto death to some, and the savour of life unto life to others, 2-Corinthians 2:16. The Targum paraphrases the words,
"either a rain of vengeance on the seas and deserts, or an impetuous rain on the trees of the mountains and hills, or a still rain of mercy on the fruitful fields and vineyards.''
(t) "in una tribu", V. L. "uni tribui", Tigurine version.

Literally, "He maketh it (the rain-cloud) find place," whether for correction, if (it be destined) for His land (that is, for the part inhabited by man, with whom God deals, as opposed to the parts uninhabited, on which rain is at other times appointed to fall, Job 38:26-27) or for mercy. "If it be destined for His land" is a parenthetical supposition [MAURER]. In English Version, this clause spoils the even balance of the antithesis between the "rod" (Margin) and "mercy" (Psalm 68:9; Genesis. 7:1-24).

Correction - To scourge or correct men by immoderate showers. Earth - The whole earth, which is said to be the Lord's, Psalm 24:1, Psalm 50:12, and so this may denote a general judgment by excessive rains inflicted upon the earth, and all its inhabitants, even the universal deluge, which came in great measure out of the clouds. Mercy - For the benefit of mankind and for the cooling of the air and improving the fruits of the earth.