Here, I. David reflects with comfort upon his own integrity, and rejoices in the testimony of his conscience that he had had his conversation in godly sincerity and not with fleshly wisdom, Co2 1:12. His deliverances were an evidence of this, and this was the great comfort of his deliverances. His enemies had misrepresented him, and perhaps, when his troubles continued long, he began to suspect himself; but, when God visibly took his part, he had both the credit and the comfort of his righteousness. 1. His deliverances cleared his innocency before men, and acquitted him from those crimes which he was falsely accused of. This he calls rewarding him according to his righteousness (Psa 18:20, Psa 18:24), that is, determining the controversy between him and his enemies, according to the justice of his cause and the cleanness of his hands, from that sedition, treason, and rebellion, with which he was charged. He had often appealed to God concerning his innocency; and now God had given judgment upon the appeal (as he always will) according to equity. 2. They confirmed the testimony of his own conscience for him, which he here reviews with a great deal of pleasure, Psa 18:21-23. His own heart knows, and is ready to attest it, (1.) That he had kept firmly to his duty, and had not departed, not wickedly, not wilfully departed, from his God. Those that forsake the ways of the Lord do, in effect, depart from their God, and it is a wicked thing to do so. But though we are conscious to ourselves of many a stumble, and many a false step taken, yet if we recover ourselves by repentance, and go on in the way of our duty, it shall not be construed into a departure, for it is not a wicked departure, from our God. (2.) That he had kept his eye upon the rule of God's commands (Psa 18:22): "All his judgments were before me; and I had a respect to them all, despised none as little, disliked none as hard, but made it my care and business to conform to them all. His statutes I did not put away from me, out of my sight, out of my mind, but kept my eye always upon them, and did not as those who, because they would quit the ways of the Lord, desire not the knowledge of those ways." (3.) That he had kept himself from his iniquity, and thereby had approved himself upright before God. Constant care to abstain from that sin, whatever it be, which most easily besets us, and to mortify the habit of it, will be a good evidence for us that we are upright before God. As David's deliverances cleared his integrity, so did the exaltation of Christ clear his, and for ever roll away the reproach that was cast upon him; and therefore he is said to be justified in the Spirit, Ti1 3:16.

II.He takes occasion thence to lay down the rules of God's government and judgment, that we may know not only what God expects from us, but what we may expect from him, Psa 18:25, Psa 18:26. 1. Those that show mercy to others (even they need mercy, and cannot depend upon the merit, no, not of their works of mercy) shall find mercy with God, Mat 5:7. 2. Those that are faithful to their covenants with God, and the relations wherein they stand to him, shall find him all that to them which he has promised to be. Wherever God finds an upright man, he will be found an upright God. 3. Those that serve God with a pure conscience shall find that the words of the Lord are pure words, very sure to be depended on and very sweet to be delight in. 4. Those that resist God, and walk contrary to him, shall find that he will resist them, and walk contrary to them, Lev 26:21, Lev 26:24.

III.Hence he speaks comfort to the humble ("Thou wilt save the afflicted people, that are wronged and bear it patiently"), terror to the proud ("Thou wilt bring down high looks, that aim high, and look with scorn and disdain upon the poor and pious"), and encouragement to himself - "Thou wilt light my candle, that is, thou wilt revive and comfort my sorrowful spirit, and not leave me melancholy; thou wilt recover me out of my troubles and restore me to peace and prosperity; thou wilt make my honour bright, which is now eclipsed; thou wilt guide my way, and make it plain before me, that I may avoid the snares laid for me; thou wilt light my candle to work by, and give me an opportunity of serving thee and the interests of thy kingdom among men."

Let those that walk in darkness, and labour under many discouragements in singing these verses, encourage themselves that God himself will be a light to them.

With the pure thou wilt show thyself pure,.... None of Adam's posterity are pure by nature; they are all defiled with sin; and though some are pure in their own eyes, they are far from being cleansed from their filthiness; such only are pure who are sanctified by the Spirit of God, have clean hearts created in them, and whose hearts are purified by faith in the blood of Christ; who are justified by Christ's righteousness, and are washed from their sins in his blood; and who, in consequence of such grace, love, pureness of heart, speak a pure language, hold the mystery of faith in a pure conscience, and with a pure conversation, and live soberly, righteously, and godly: and whereas God is a pure and holy Being, his perfections, works, and word, are pure; he shows himself to be so to such persons, by providing for the honour of his purity and holiness in their redemption, sanctification, and salvation; by making all things to be pure to them; by granting them his presence, and blessing them with the vision of himself here and hereafter; see Mat 5:8; this may likewise be understood of Christ, who, in his human nature, is pure from all sin, both original and actual: he indeed took upon him the sins of his people, and bore them, and made satisfaction for them, and brought in everlasting righteousness; which being done, God has showed himself pure to him, by justifying, acquitting, and discharging him from all such sins; by accepting his righteousness, and imputing it to those for whom he wrought it;

and with the froward thou wilt show thyself froward; or "thou wrestlest" (b), or wilt contend with them until they are destroyed: the same word is here used which Naphtali has his name from, Gen 30:8. The froward are such as are of perverse dispositions, and of stubborn and obstinate tempers, and whose ways are crooked and distorted; and such were the people of the Jews in the times of Moses, and of Christ, Deu 32:5; and who seem here to be designed; even the Jews in Christ's time, who were just the reverse of the above characters, were cruel and unmerciful, faithless and hypocritical, filthy and pure, disbelieved the Messiah, rejected and crucified him, were contrary to God, and to all men; and therefore God walked contrary to them, as he threatened, Lev 26:27; the same as showing himself froward to them; for God is not froward and perverse in himself, nor in his ways, which are all equal, just, and pure: and though there is one and the same word used in our version, yet there are two different words in the Hebrew text; the same word that is used of the froward is not used of God; that which is used of God, as before observed, signifies wrestling, and designs God's contending with the people of the Jews, in a way of wrath and fury, which came upon them to the uttermost, and issued in their entire ruin as a people and nation; the words here had their fulfilment in the destruction of Jerusalem.

(b) "eluctaris", Junius & Tremellius; "colluctaris", Aben Ezra; "reluctaris", Gejerus; "certas", Schmidt.

God renders to men according to their deeds in a penal, not vindictive, sense (Lev 26:23-24).

merciful--or, "kind" (Psa 4:3).