To shew that the LORD is upright: he is my rock, and there is no unrighteousness in him.

that they may shew, That the Lord our God is righteous, and there is no iniquity in him.

To declare that upright is Jehovah my rock, And there is no perverseness in Him!

For a sign that the Lord is upright; he is my Rock, there is no deceit in him.

They shall still bring forth fruit in old age; They shall be full of sap and richness;

That they may show that Jehovah is upright. It is evident from this verse that the great object of the Psalmist is, to allay that disquietude of mind which we are apt to feel under the disorder which reigns apparently in the affairs of this world; and to make us cherish the expectation, (under all that may seem severe and trying in our lot, and though the wicked are in wealth and power, flourish, and abound in places and distinctions,) that God will bring light and order eventually out of confusion. That they may show, it is said particularly, that the Lord is upright; for through the influence of our corruption we are apt to conclude, when things do not proceed as we would wish in the world, that God is chargeable not only with neglect but with unrighteousness, in abandoning his people, and tolerating the commission of sin. When God displays his justice in proceeding to execute vengeance upon the wicked, it will be seen at once, that any prosperity which they enjoyed was but the forerunner of a worse destruction in reserve for them. The Psalmist, in calling God his rock, shows a second time that he reckoned himself amongst the number of those in whom God would illustrate his justice by extending towards them his protection.

To shew that the Lord is upright - That is, This will be a proof that God is faithful to his promises; that he is the true friend of his people. The fact that they live long - that they are happy and useful even in old age, will be a demonstration that God is the friend of virtue, and that he deals with people according to their character.
He is my rock - He is my defense; that which constitutes my security. See the notes at Psalm 18:2. This is language of strong confidence in view of all that is said in the psalm.
And there is no unrighteousness in him - This is said in the most absolute form - implying the most entire confidence. God is altogether to be trusted. There is no evil or wrong in his character or in his dealings. In all respects he is worthy of confidence: "worthy" to be loved, trusted, adored, obeyed, by the inhabitants of all worlds. What a sublime thought is this! What a consolatory truth! What would the universe be if God, a Being of infinite POWER, were not a Being of perfect RIGHTEOUSNESS, and could not be trusted by the creatures which he has made!

To show that the Lord is upright - Such persons show how faithful God is to his promises, how true to his word, how kind to them who trust in him. He is the Rock, the Fountain, whence all good comes.
There is no unrighteousness in him - He does nothing evil, nothing unwise, nothing unkind. He is both just and merciful.

To show that the Lord is upright,.... Or righteous, that is, faithful; as he is in his counsels, covenant, and promises, which he makes good by causing his people to grow and flourish, and become fruitful; by carrying on the work of grace upon their souls, and by preserving them to the end safe to his kingdom and glory; by all which it appears that he does not and will not suffer his faithfulness to fail: the Targum is,
"that the inhabitants of the earth may show, &c.''
he is my Rock; the psalmist sets his seal to the truth of God's faithfulness, firmness, and constancy, calling him a Rock for his strength and stability, and claiming his interest in him; declaring he found him to be so by experience,
even the Rock whose work is perfect; who always completes what he undertakes, and finishes what he begins, and will not forsake the work of his own hands:
just and right is he; the Rock of ages, that remains firm, steadfast, and unalterable in all generations:
and there is no unrighteousness in him; as not in his sovereign acts of grace, so neither in his providential dispensations, either towards good men or bad men; not in suffering the wicked to prosper, as in Psalm 92:7, and the righteous to be afflicted; nor in punishing bad men here, or hereafter; nor in justifying sinners by the righteousness of his Son, and giving them the crown of righteousness at the last day: all his proceedings are in the most just and equitable manner; see Romans 9:14.

and they thus declare God's glory as their strong and righteous ruler.