We have three things in these verses: -

I.The believing acknowledgment which David makes of God's goodness to his people in general, Psa 31:19, Psa 31:20.

1.God is good to all, but he is, in a special manner, good to Israel. His goodness to them is wonderful, and will be, to eternity, matter of admiration: O how great is thy goodness! How profound are the counsels of it! how rich are the treasures of it! how free and extensive are the communications of it! Those very persons whom men load with slanders God loads with benefits and honours. Those who are interested in this goodness are described to be such as fear God and trust in him, as stand in awe of his greatness and rely on his grace. This goodness is said to be laid up for them and wrought for them. (1.) There is a goodness laid up for them in the other world, an inheritance reserved in heaven (Pe1 1:4), and there is a goodness wrought for them in this world, goodness wrought in them. There is enough in God's goodness both for the portion and inheritance of all his children when they come to their full age, and for their maintenance and education during their minority. There is enough in bank and enough in hand. (2.) This goodness is laid up in his promise for all that fear God, to whom assurance is given that they shall want no good thing. But it is wrought, in the actual performance of the promise, for those that trust in him - that by faith take hold of the promise, put it in suit, and draw out to themselves the benefit and comfort of it. If what is laid up for us in the treasures of the everlasting covenant be not wrought for us, it is our own fault, because we do not believe. But those that trust in God, as they have the comfort of his goodness in their own bosoms, so they have the credit of it (and the credit of an estate goes far with some); it is wrought for them before the sons of men. God's goodness to them puts an honour upon them and rolls away their reproach; for all that see them shall acknowledge them, that they are the seed which the Lord hath blessed, Isa 61:9.

2.God preserves man and beast; but he is, in a special manner, the protector of his own people (Psa 31:20): Thou shalt hide them. As his goodness is hid and reserved for them, so they are hid and preserved for it. The saints are God's hidden ones. See here, (1.) The danger they are in, which arises from the pride of man and from the strife of tongues; proud men insult over them and would trample on them and tread them down; contentious men pick quarrels with them; and, when tongues are at strife, good people often go by the worst. The pride of men endangers their liberty; the strife of tongues in perverse disputings endangers truth. But, (2.) See the defence they are under: Thou shalt hide them in the secret of thy presence, in a pavilion. God's providence shall keep them safe form the malice of their enemies. He has many ways of sheltering them. When Baruch and Jeremiah were sought for the Lord hid them, Jer 36:26. God's grace shall keep them safe from the evil of the judgments that are abroad; to them they have no sting; and they shall hidden in the day of the Lord's anger, for there is no anger at them. His comforts shall keep them easy and cheerful; his sanctuary, where they have communion with him, shelters then from the fiery darts of terror and temptation; and the mansions in his house above shall be shortly, shall be eternally, their hiding-place from all danger and fear.

II.The thankful returns which David makes for God's goodness to him in particular, Psa 31:21, Psa 31:22. Having admired God's goodness to all the saints, he here owns how good he had found him. 1. Without were fightings; but God had wonderfully preserved his life: "He has shown me his marvellous loving-kindness, he has given me an instance of his care for me and favour to me, beyond what I could have expected." God's loving-kindness to his people, all things considered, is wonderful; but some instances of it, even in this world, are in a special manner marvelous in their eyes; as this here, when God preserved David from the sword of Saul, in caves and woods, as safe as if he had been in a strong city. In Keilah, that strong city, God showed him great mercy, both in making him an instrument to rescue the inhabitants out of the hands of the Philistines and then in rescuing him from the same men who would have ungratefully delivered him up into the hand of Saul, Sa1 23:5, Sa1 23:12. This was marvellous loving-kindness indeed, upon which he writes, with wonder and thankfulness, Blessed be the Lord. Special preservations call for particular thanksgivings. 2. Within were fears; but God was better to him than his fears, Psa 31:22. He here keeps an account, (1.) Of his own folly, in distrusting God, which he acknowledges, to his shame. Though he had express promises to build upon, and great experience of God's care concerning him in many straits, yet he had entertained this hard and jealous thought of God, and could not forbear telling it him to his face. "I am cut off before thy eyes; thou hast quite forsaken me, and I must not expect to be looked upon or regarded by thee any more. I shall one day perish by the hand of Saul, and so be cut off before thy eyes, be ruined while thou lookest on," Sa1 27:1. This he said in his flight (so some read it), which denotes the distress of his affairs. Saul was just at his back, and ready to seize him, which made the temptation strong. In my haste (so we read it), which denotes the disturbance and discomposure of his mind, which made the temptation surprising, so that it found him off his guard. Note, It is a common thing to speak amiss when we speak in haste and without consideration; but what we speak amiss in haste we must repent of at leisure, particularly that which we have spoken distrustfully of God. (2.) Of God's wonderful goodness to him notwithstanding. Though his faith failed, God's promise did not: Thou hearest the voice of my supplication, for all this. He mentions his own unbelief as a foil to God's fidelity, serving to make his loving-kindness the more marvellous, the more illustrious. When we have thus distrusted God he might justly take us at our word, and bring our fears upon us, as he did on Israel, Num 14:28; Isa 66:4. But he has pitied and pardoned us, and our unbelief has not made his promise and grace of no effect; for he knows our frame.

III.The exhortation and encouragement which he hereupon gives to all the saints, Psa 31:23, Psa 31:24. 1. He would have them set their love on God (Psa 31:23): O love the Lord! all you his saints. Those that have their own hearts full of love to God cannot but desire that others also may be in love with him; for in his favour there is no need to fear a rival. It is the character of the saints that they do love God; and yet they must still be called upon to love him, to love him more and love him better, and give proofs of their love. We must love him, not only for his goodness, because he preserves the faithful, but for his justice, because he plentifully rewards the proud doer (who would ruin those whom he preserves), according to their pride. Some take it in a good sense; he plentifully rewards the magnificent (or excellent) doer, that is daringly good, whose heart, like Jehoshaphat's, is lifted up in the ways of the Lord. He rewards him that does well, but plentifully rewards him that does excellently well. 2. He would have them set their hope in God (Psa 31:24): "Be of good courage; have a good heart on it; whatever difficulties or dangers you may meet with, the God you trust in shall by that trust strengthen your heart." Those that hope in God have reason to be of good courage, and let their hearts be strong, for, as nothing truly evil can befal them, so nothing truly good for them shall be wanting to them.

In singing this we should animate ourselves and one another to proceed and persevere in our Christian course, whatever threatens us, and whoever frowns upon us.

Blessed be the Lord,.... A form of thanksgiving, in which the psalmist calls upon himself and others to bless and praise the Lord for the singular mercy granted him, expressed in the next clause; See Gill on Psa 18:46;

for he hath showed me his marvellous kindness in a strong city; either in the city Keilah, so Jarchi; a city which had gates and bars, where Saul thought he had David safe, and he could not escape his hands; but notwithstanding that, and though the inhabitants of that place intended to deliver him up, yet he was marvellously saved; as he also was from the Ziphites; and when Saul and his army had encompassed him about, by a surprising incident, a messenger coming to Saul just as he was about to seize him, informing him that the Philistines had invaded the land, Sa1 23:7. Or the city of Jerusalem, which was fortified both by nature and art, whither he was brought and placed as king, and enjoyed rest from all his enemies round about him, Sa2 5:6. Or this may spiritually design the church of God, which is called a strong city, being built on Christ the Rock, and having salvation for walls and bulwarks, Isa 26:1, where the Lord displays his banner of love, makes discoveries of his marvellous kindness, and commands his blessing for evermore. Some render it "as in a strong city" (g), and take the sense to be, that he was safe, through the kindness of God showed to him in the salvation of him, as if he was in a fortified city (h), and this was marvellous in his eyes, as every instance of providential goodness is to the people of God; especially his lovingkindness showed in spiritual things, in choosing them in Christ, saving them by him, regenerating them by his Spirit, and taking them into his family; which love is free and sovereign, distinguishing, unchangeable, from everlasting to everlasting; and so wonderful and astonishing; and which was hid in God until revealed; and sometimes the manifestations of it are withdrawn, and then it is showed again, and fresh discoveries of it are made, and effects of it applied, and the blessings of it bestowed, which occasion thankfulness.

(g) "ut in civitate munita", Junius & Tremellius, Piscator; Michaelis. (h) Aben Ezra, Kimchi, & Ben Melech in loc.

the secret of thy presence--or, covering of Thy countenance; the protection He thus affords; compare Psa 27:5 for a similar figure; "dwelling" used there for "presence" here. The idea of security further presented by the figure of a tent and a fortified city [Psa 31:21].