The assaults of enemies and the devastations of pestilence are taken in vv. 5, 6, as types of all perils. These evils speak of a less artificial stage of society than that in which our experience moves, but they serve us as symbols of more complex dangers besetting outward and inward life. "The terror of the night" seems best understood as parallel with the "arrow that flies by day," in so far as both refer to actual attacks by enemies. Nocturnal surprises were favourite methods of assault in early warfare. Such an explanation is worthier than the supposition that the psalmist means demons that haunt the night. In ver. 6 Pestilence is personified as stalking, shrouded in darkness, the more terrible because it strikes unseen. Ver. 6_b_ has been understood, as by the Targum and LXX., to refer to demons who exercise their power in noonday. But this explanation rests upon a misreading of the word rendered "devastates." The other translated "sickness" is only found, besides this place, in Deut. xxxii. 24 ("destruction") and Isa. xxviii. 2 ("a destroying storm," lit. a storm of destruction), and in somewhat different form in Hosea xiii. 14. It comes from a root meaning _to cut_, and seems here to be a synonym for pestilence. Baethgen sees in "the arrow by day" the fierce sunbeams, and in "the _heat_ (as he renders) which rages at noonday" the poisonous simoom. The trustful man, sheltered in God, looks on while thousands fall round him, as Israel looked from their homes on the Passover night, and sees that there is a God that judges and recompenses evil-doers by evil suffered. Heartened by these great assurances, the single voice once more declares its trust. Ver. 9_a_ is best separated from _b_, though Hupfeld here again assumes that "thou hast said" has fallen out between "For" and "Thou." This second utterance of trust is almost identical with the first. Faith has no need to vary its expression. "Thou, Jehovah, art my refuge" is enough for it. God's mighty name and its personal possession of all which that name means, as its own hiding-place, are its treasures, which it does not weary of recounting. Love loves to repeat itself. The deepest emotions, like song-birds, have but two or three notes, which they sing over and over again all the long day through. He that can use this singer's words of trust has a vocabulary rich enough.