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 (2 Samuel 22:50). 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.
2 Samuel 22:51 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.
