That assurance prepares the way for the noble burst of thanksgiving, as for accomplished deliverance, which ends the psalm, springing up in a joyous outpouring of melody, like a lark from a bare furrow. But there is no such change of tone as to warrant the supposition that these last verses (19-24) are either the psalmist's later addition or the work of another, nor do they oblige us to suppose that the whole psalm was written after the peril which it commemorates had passed. Rather the same voice which triumphantly rings out in these last verses has been sounding in the preceding, even in their saddest strains. The ear catches a twitter hushed again and renewed more than once before the full song breaks out. The psalmist has been absorbed with his own troubles till now, but thankfulness expands his vision, and suddenly there is with him a multitude of fellow-dependants on God's goodness. He hungers alone, but he feasts in company. The abundance of God's "goodness" is conceived of as a treasure stored, and in part openly displayed, before the sons of men. The antithesis suggests manifold applications of the contrast, such as the inexhaustibleness of the mercy which, after all revelation, remains unrevealed, and, after all expenditure, has not perceptibly diminished in its shining mass, as of bullion in some vault; or the varying dealings of God, who sometimes, while sorrow is allowed to have its scope, seems to keep His riches of help under lock and key, and then again flashes them forth in deeds of deliverance; or the difference between the partial unfolding of these on earth and the full endowment of His servants with "riches in glory" hereafter. All these carry the one lesson that there is more in God than any creature or all creatures have ever drawn from Him or can ever draw. The repetition of the idea of hiding in ver. 20 is a true touch of devout poetry. The same word is used for laying up the treasure and for sheltering in a pavilion from the jangle of tongues. The wealth and the poor men who need it are stored together, as it were; and the place where they both lie safe is God Himself. How can they be poor who are dwelling close beside infinite riches? The psalmist has just prayed that God would make His face to shine upon him; and now he rejoices in the assurance of the answer, and knows himself and all like-minded men to be hidden in that "glorious privacy of light," where evil things cannot live. As if caught up to and "clothed with the sun," he and they are beyond the reach of hostile conspiracies, and have "outsoared the shadow of" earth's antagonisms. The great thought of security in God has never been more nobly expressed than by that magnificent metaphor of the light inaccessible streaming from God's face to be the bulwark of a poor man.
The personal tone recurs for a moment in vv. 21, 22, in which it is doubtful whether we hear thankfulness for deliverance anticipated as certain and so spoken of as past, since it is as good as done, or for some recently experienced marvel of loving-kindness, which heartens the psalmist in present trouble. If this psalm is David's, the reference may be to his finding a city of refuge, at the time when his fortunes were very low, in Ziklag, a strange place for a Jewish fugitive to be sheltered. One can scarcely help feeling that the allusion is so specific as to suggest historical fact as its basis. At the same time it must be admitted that the expression may be the carrying on of the metaphor of the hiding in a pavilion. The "strong city" is worthily interpreted as being God Himself, though the historical explanation is tempting. God's mercy makes a true man ashamed of his doubts, and therefore the thanksgiving of ver. 21 leads to the confession of ver. 22. Agitated into despair, the psalmist had thought that he was "cut off from God's eyes"--_i.e._, hidden so as not to be helped--but the event has showed that God both heard and saw him. If alarm does not so make us think that God is blind to our need and deaf to our cry as to make us dumb, we shall be taught the folly of our fears by His answers to our prayers. These will have a voice of gentle rebuke, and ask us, "O thou of little faith, wherefore didst thou doubt?" He delivers first, and lets the deliverance stand in place of chiding.