The Davidic authorship of this great hymn has been admitted even by critics who are in general too slow to recognise it. One of these says that 'there is no Israelite king to whom the expressions in the psalm apply so closely as to David.' The favourite alternative theory that the speaker is the personified nation is hard to accept. The voice of individual trust and of personal experience sounds clear in the glowing words. Two editions of the hymn are preserved for us, -- in Psalm xviii. and 2 Samuel. Slight variations exist in the two copies, which may probably be merely accidental. Nothing important depends on them. The text begins with the closing words of a description of God's arming the singer for his victories, and goes on to paint the tumult of battle and the rout of the foe (verses 40-43); then follows triumphant expectation of future wider victories (verses 44-46); and that leads up to the closing burst of grateful praise (verses 47-51).
I. We are not to forget that what is described in verses 40-43 is a literal fight, with real swords against very real enemies. We may draw lessons of encouragement from it for our conflict with spiritual wickednesses, but we must not lose sight of the bloody combat with flesh and blood which the singer had waged. He felt that God had braced his armour on him, had given him the impenetrable 'shield' which he wore on his arm, and had strengthened his arms to bend the 'bow of steel.' We see him in swift pursuit, pressing hard on the flying foe, crushing them with his fierce charge, trampling them under foot. 'I did beat them small as the dust of the earth.' His blows fell like those of a great pestle, pulverising some substance in a mortar. 'I did stamp them as the mire of the streets,' -- a vivid picture of trampling down the prostrate wretches, for which Psalm xviii. gives the less picturesque variant, 'did cast them out.' In their despair the fugitives shriek aloud for God's help, and the Psalmist has a stern joy in knowing their cries to be unheard.
Now, such delight in an enemy's despair and destruction, such gratification at the vanity of his prayers, are far away from being Christian sentiments, and the gulf is not wholly bridged by the consideration that David felt himself to be God's Anointed, and enmity to him to be, consequently, treason against God. His feelings were most natural and entirely consistent with the stage of revelation in which he lived. They were capable of being purified into that triumph in the victory of good and the ruin of evil without which there is no vigorous sympathy with Christ's conflict. They kindle, by their splendid energy and condensed rapidity, an answering glow even in readers so far away from the scene as we are. But still they do belong to a lower level of feeling, and result from a less full revelation than belongs to Christianity. The light of battle which blazes in them is not the fire which Jesus longed to kindle on earth.
But we may well take a pattern from the stern soldier's recognition that all his victory was due to God alone. The strength that he put forth was God's gift. It was God who subdued the insurgents, not David. The panic which made the foe take to flight was infused into them by God. No name but Jehovah's was to be carved on the trophy reared on the battlefield. The human victor was but the instrument of the divine Conqueror. Such lowly reference of all our power and success to Him will save us from overweening self-adulation, and is the surest way to retain the power which He gives, and which is lost most surely when we take the credit of it to ourselves.
II. The enemies thus far have been from among his own subjects, but in verses 44-46 a transition is made to victory over 'strangers'; that is, foreign nations. The triumph over 'the strivings of my people' heartens the singer to expect that he will be' head of the nations.' The other version of the hymn (Psalm xviii.) reads simply 'the people.'
The picture of hasty surrender 'as soon as they hear of me' is graphic. His very name conquers. 'The strangers shall submit themselves unto me' is literally 'shall lie,' or yield feigned obedience. They 'fade away' as if withered by the hot wind of the desert. 'They shall come limping' (as the word here used signifies), as if wounded in the fight, for which Psalm xviii. reads 'trembling.'
Now this vision of extended conquests, based as it is on past smaller victories, carries valuable lessons. David here lays hold of the great promises to his house of a wide dominion, and expects the beginnings of their fulfilment to himself. And he did extend his conquests beyond the territory of Israel. But we may take the hope as an instance in a particular direction of what should be the issue of all experience of God's mercies. 'To-morrow shall be as this day, and much more abundant.' Smaller victories will be followed by greater. Our reception of God's favouring help should widen our anticipations. Our gratitude to Him should be 'a lively sense of favours to come.' Progressive victory should be the experience of every believer.
We may see, too, dimly apparent through the large hope of the Psalmist- King, the prophecy of the worldwide victories of his Son, in whom the great promises of a dominion 'from sea to sea, and from the river unto the ends of the earth,' are fulfilled.
III. Verses 46-51 make a noble close to a noble hymn, in which the singer's strong wing never flags, nor the rush of thought and feeling ever slackens. In it, even more absolutely than in the rest of the psalm, his victory is all ascribed to Jehovah. He alone acts, David simply receives. To have learned by experience that' He lives,' and is 'my Rock,' and to gather all the feelings excited by the retrospect of a long life into 'Blessed be my Rock,' is to have reaped and garnered the richest harvest which earth can yield. So at last sings the man whose early years had been full of struggles and privations. A morning of tempest has cleared into sunny evening calm, as it will with us all if the tempest blows us into our true shelter.
This psalm begins with a rapturous heaping together of the precious names of God, as the singer has had them revealed to him by experience. Foremost among these stands that one, 'my Rock,' which is caught up again in this closing burst of thanksgiving. That great Rock towers unchangeable above fleeting things. The river runs past its base, the woods nestling at its feet bud, and shed their pride of foliage, but it stands the same. David had many a time hid in 'the clefts of the rocks' in his years of wandering, and the figure is eloquent on his lips.
These closing strains gather together once more the main points of the previous verses, his deliverance from domestic foes, and his conquests over external enemies. These are wholly God's work. True thankfulness delights to repeat its acknowledgments. God does not weary of giving, we should not weary of praising the Giver and His gifts. We renew our enjoyment of our long-past mercies by reiterating our thankfulness for them. They do not die as long as gratitude keeps their remembrance green.
But the Psalmist's experience impels him to a vow (verse 50). He will give thanks to God among the nations. God's mercies bind, and, if rightly felt, will joyfully impel, the receiver to spread His name as far as his voice can reach. Love is sometimes silent, but gratitude must speak. The most unmusical voice is tuned to melody by God's great blessings received and appreciated, and they need never want a theme who can tell what the Lord has done for their souls. 'Then shall... the tongue of the dumb sing.' A dumb Christian is a monstrosity. We are 'the secretaries of His praise,' and have been saved ourselves that we may declare His goodness.
Verse 51 has been supposed by some to be a liturgical addition, on the ground that, if David were the author, he would not be likely to name himself thus. But there does not seem to be anything unnatural in his mentioning himself by name in such a connection, and the reference to his dynasty, based as it is on Nathan's promise, is most fitting. The last thought about his mercies which the humble gratitude of the Psalmist utters is that they were not given to him for any good in himself, nor to be selfishly enjoyed, but that they were bestowed on him because of the place that he filled in the divine purposes, and belonged to 'his seed' as truly as to himself. So lowly had his prosperity made him. So truly had he sunk himself in his office, and in the great things that God meant to do through him and his house. We know better than David did what these were, and how the promise on which he rested his hopes of the duration of his house is fulfilled in his Son, whose kingdom is an everlasting kingdom, and who bears God's name to all the nations.