With ver. 19 the psalmist passes to the fourth day, but thinks of moon and sun only in relation to the alternation of day and night as affecting creatural life on earth. The moon is named first, because the Hebrew day began with the evening. It is the _measurer_, by whose phases seasons (or, according to some, _festivals_) are reckoned. The sun is a punctual servant, knowing the hour to set and duly keeping it. "Thou appointest darkness and it is night." God wills, and His will effects material changes. He says to His servant Night, "Come," and she "comes." The psalmist had peopled the vales and mountains of his picture. Everywhere he had seen life fitted to its environment; and night is populous too. He had outlined swift sketches of tame and wild creatures, and now he half shows us beasts of prey stealing through the gloom. He puts his finger on two characteristics--their stealthy motions, and their cries which made night hideous. Even their roar was a kind of prayer, though they knew it not; it was God from whom they sought their food. It would not have answered the purpose to have spoken of "all the loves, Now sleeping in those quiet groves." The poet desired to show how there were creatures that found possibilities of happy life in all the variety of conditions fashioned by the creative Hand, which was thus shown to be moved by Wisdom and Love. The sunrise sends these nocturnal animals back to their dens, and the world is ready for man. "The sun looked over the mountain's rim," and the beasts of prey slunk to their lairs, and man's day of toil began--the mark of his pre-eminence, God's gift for his good, by which he uses creation for its highest end and fulfils God's purpose. Grateful is the evening rest when the day has been filled with strenuous toil.
The picture of earth and its inhabitants is now complete, and the dominant thought which it leaves on the psalmist's heart is cast into the exultant and wondering exclamation of ver. 24. The variety as well as multitude of the forms in which God's creative idea is embodied, the Wisdom which shapes all, His ownership of all, are the impressions made by the devout contemplation of Nature. The scientist and the artist are left free to pursue their respective lines of investigation and impression; but scientist and artist must rise to the psalmist's point of view, if they are to learn the deepest lesson from the ordered kingdoms of Nature and from the beauty which floods the world.
With the exclamation in ver. 24 the psalmist has finished his picture of the earth, which he had seen as if emerging from the abyss, and watched as it was gradually clothed with fertility and peopled with happy life. He turns, in vv. 25, 26, to the other half of his Vision of Creation, and portrays the gathered and curbed waters which he now calls the "sea." As always in Scripture, it is described as it looks to a landsman, gazing out on it from the safe shore. The characteristics specified betray unfamiliarity with maritime pursuits. The far-stretching roll of the waters away out to the horizon, the mystery veiling the strange lives swarming in its depths, the extreme contrasts in the magnitude of its inhabitants, strike the poet. He sees "the stately ships go on." The introduction of these into the picture is unexpected. We should have looked for an instance of the "small" creatures, to pair off with the "great" one, Leviathan, in the next words. "A modern poet," says Cheyne, _in loc._, "would have joined the mighty whale to the fairy nautilus." It has been suggested that "ship" here is a name for the nautilus, which is common in the Eastern Mediterranean. The suggestion is a tempting one, as fitting in more smoothly with the antithesis of _small_ and _great_ in the previous clause. But, in the absence of any proof that the word has any other meaning than "ship," the suggestion cannot be taken as more than a probable conjecture. The introduction of "ships" into the picture is quite in harmony with the allusions to man's works in the former parts of the psalm, such as ver. 23, and possibly ver. 14. The psalmist seems to intend to insert such reference to man, the only toiler, in all his pictures. "Leviathan" is probably here the whale. Ewald, Hitzig, Baethgen, Kay, and Cheyne follow the LXX. and Vulgate in reading "Leviathan whom Thou hast formed to sport with him," and take the words to refer to Job xli. 5. The thought would then be that God's power can control the mightiest creatures' plunges; but "the two preceding 'there's are in favour of the usual interpretation, 'therein'" (Hupfeld), and consequently of taking the "sporting" to be that of the unwieldy gambols of the sea-monster.