What's this saying?

Psa 24:1 A Psalm of David. The earth is the LORD'S, and the fulness thereof; the world, and they that dwell therein.
Psa 24:2 For he hath founded it upon the seas, and established it upon the floods.
Psa 24:3 Who shall ascend into the hill of the LORD? or who shall stand in his holy place?
Psa 24:4 He that hath clean hands, and a pure heart; who hath not lifted up his soul unto vanity, nor sworn deceitfully.
Psa 24:5 He shall receive the blessing from the LORD, and righteousness from the God of his salvation.
Psa 24:6 This is the generation of them that seek him, that seek thy face, O Jacob. Selah.
Psa 24:7 Lift up your heads, O ye gates; and be ye lift up, ye everlasting doors; and the King of glory shall come in.
Psa 24:8 Who is this King of glory? The LORD strong and mighty, the LORD mighty in battle.
Psa 24:9 Lift up your heads, O ye gates; even lift them up, ye everlasting doors; and the King of glory shall come in.
Psa 24:10 Who is this King of glory? The LORD of hosts, he is the King of glory. Selah.