"Who may ascend?" was a picturesquely appropriate question for singers toning upwards, and "who may stand?" for those who hoped presently to enter the sacred presence. The Ark which they bore had brought disaster to Dagon's temple, so that the Philistine lords had asked in terror, "Who is able to stand before this holy Lord God?" and at Beth-shemesh its presence had been so fatal that David had abandoned the design of bringing it up and said, "How shall the ark of the Lord come to me?" The answer, which lays down the qualifications of true dwellers in Jehovah's house, may be compared with the similar outlines of ideal character in Psalm xv. and Isa. xxxiii. 14. The one requirement is purity. Here that requirement is deduced from the majesty of Jehovah, as set forth in vv. 1, 2, and from the designation of His dwelling as "holy." This is the postulate of the whole Psalter. In it the approach to Jehovah is purely spiritual, even while the outward access is used as a symbol; and the conditions are of the same nature as the approach. The general truth implied is that the character of the God determines the character of the worshippers. Worship is supreme admiration, culminating in imitation. Its law is always "They that make them are like unto them; so is every one that trusteth in them." A god of war will have warriors, and a god of lust sensualists, for his devotees. The worshippers in Jehovah's holy place must be holy. The details of the answer are but the echoes of a conscience enlightened by the perception of His character. In ver. 4 it may be noted that of the four aspects of purity enumerated the two central refer to the inward life (_pure heart; lifts not his desire unto vanity_), and these are embedded, as it were, in the outward life of deeds and words. Purity of act is expressed by "clean hands"--neither red with blood, nor foul with grubbing in dunghills for gold and other so-called good. Purity of speech is condensed into the one virtue of truthfulness (_swears not to a falsehood_). But the outward will only be right if the inward disposition is pure, and that inward purity will only be realised when desires are carefully curbed and directed. As is the desire, so is the man. Therefore the prime requisite for a pure heart is the withdrawal of affection, esteem, and longing from the solid-seeming illusions of sense. "Vanity" has, indeed, the special meaning of _idols_, but the notion of earthly good apart from God is more relevant here.