Psalm 24
The whole earth belongs to God, so who may come near Him? Clean hands, a pure heart, no idols, no false oaths. Then the gates are told to lift up their heads for the King of Glory, "mighty in battle." Holiness and joy belong together: the King comes in.
"He who has clean hands and a pure heart, who does not lift up his soul to an idol or swear deceitfully." (Psalm 24:4)