True thankfulness is expansive, and joy craves for sympathy. So the psalmist invites other voices to join his song, since he is sure that others there are who have shared his experience. It has been but one instance of a universal law. He is not the only one whom Jehovah has treated with loving-kindness, and he would fain hear a chorus supporting his solo. Therefore he calls upon "the favoured of God" to swell the praise with harp and voice and to give thanks to His "holy memorial," _i.e._ the name by which His deeds of grace are commemorated. The ground of their praise is the psalmist's own case generalised. A tiny mirror may reflect the sun, and the humblest person's history, devoutly pondered, will yield insight into God's widest dealings. This, then, is what the psalmist had learned in suffering, and wishes to teach in song: that sorrow is transient and joy perennial. A cheerful optimism should be the fruit of experience, and especially of sorrowful experience. The antitheses in ver. 5 are obvious. In the first part of the verse "anger" and "favour" are plainly contrasted, and it is natural to suppose that "a moment" and "life" are so too. The rendering, then, is, "A moment passes in His anger, a life [_i.e._, a lifetime] in His favour." Sorrow is brief; blessings are long. Thunderstorms occupy but a small part of summer. There is usually less sickness than health in a life. But memory and anticipation beat out sorrow thin, so as to cover a great space. A little solid matter, diffused by currents, will discolour miles of a stream. Unfortunately we have better memories for trouble than for blessing, and the smart of the rose's prickles lasts longer in the flesh than its fragrance in the nostril or its hue in the eye. But the relation of ideas here is not merely that of contrast. May we not say that just as the "moment" is included in the "life," so the "anger" is in the "favour"? Probably that application of the thought was not present to the psalmist, but it is an Old Testament belief that "whom the Lord loveth He chasteneth," and God's anger is the aversion of holy love to its moral opposite. Hence comes the truth that varying and sometimes opposite Divine methods have one motive and one purpose, as the same motion of the earth brings summer and winter in turn. Since the desire of God is to make men partakers of His holiness, the root of chastisement is love, and hours of sorrow are not interruptions of the continuous favour which fills the life.
A like double antithesis moulds the beautiful image of the last clause. Night and morning are contrasted, as are weeping and joy; and the latter contrast is more striking, if it be observed that "joy" is literally a "joyful shout," raised by the voice that had been breaking into audible weeping. The verb used means to lodge for a night, and thus the whole is a picture of two guests, the one coming, sombre-robed, in the hour befitting her, the other, bright-garmented, taking the place of the former, when all things are dewy and sunny, in the morning. The thought may either be that of the substitution of joy for sorrow, or of the transformation of sorrow into joy. No grief lasts in its first bitterness. Recuperative forces begin to tell by slow degrees. "The low beginnings of content" appear. The sharpest-cutting edge is partially blunted by time and what it brings. Tender green drapes every ruin. Sorrow is transformed into something not undeserving of the name of joy. Griefs accepted change their nature. "Your sorrow shall be turned into joy." The man who in the darkness took in the dark guest to sit by his fireside finds in the morning that she is transfigured, and her name is Gladness. Rich vintages are gathered on the crumbling lava of the quiescent volcano. Even for irremediable losses and immedicable griefs, the psalmist's prophecy is true, only that for these "the morning" is beyond earth's dim dawns, and breaks when this night which we call life, and which is wearing thin, is past. In the level light of that sunrise, every raindrop becomes a rainbow, and every sorrow rightly--that is, submissively--borne shall be represented by a special and particular joy.