Such ways of describing God's work in Nature or His providence are partly, of course, due to the fact (often overlooked by the half-educated) that the Psalms are poetry and not prose. For the same reason inanimate objects are personified: "the earth trembled at the look of Him," "the mountains skipped like lambs"; the mythical "Leviathan" appears both as a title of Egypt (lxxiv. 15) and as an actual monster of the deep (civ. 26). God Himself, again, is spoken of in language that might seem more appropriate to man. He is "provoked," and "tempted." He awakes "like a giant refreshed with wine." He is called upon, not to sleep nor to forget, to avenge, to "bow the heavens and come down." Nor do the Psalms in their literal meaning rise always above the current and imperfect religious conceptions of their time. The moral difficulties involved in this will be considered a little later, but it may be interesting to point out here some examples which bear on {25} the progressiveness of revelation in the Old Testament by which heathen ideas became, under God's guidance, "stepping-stones to higher things." The Psalms seem sometimes to speak as if "the gods of the heathen" really existed and were in some way rivals of the God of Israel, universal and supreme though He is acknowledged to be. They are spoken of as "devils" as well as idols. They are called upon to "worship Him" (_cf._ cvi. 36, xcvii. 7, 9, cxxxviii. i). Again, the Psalmists' horizon is, for the most part, limited to this present life, which is regarded as if it were the chief, almost the only, scene in which moral retribution would be worked out. And occasionally there appears the primitive Hebrew idea of the after-world as the vague and gloomy Sheol, like the shadowy Hades of Homer, where the dead "go down into silence," where, instead of purpose and progress, there is but a dawnless twilight, the land "without any order" of Job (xlix., lxxxviii., cxv. 17).