What does Psalm 110:2 mean?

The prior verse (Psalm 110:1) records a statement with enormous implications. David refers to two Beings using terms which can both refer to God. The first, Yahweh, tells the second, Adonai, to take a place of power and honor before experiencing total victory. Here, David continues to provide details indicating this Adonai—or "Lord"—is the Messiah. The "Lord" indicated here is Yahweh, or YHWH, a term only used for God (Exodus 3:15). New Testament writers explain how this implies that the Messiah is divine (Matthew 22:41–46; Hebrews 1:13).

Where the earlier statement indicates divinity, this verse declares earthly rule. Zion is a reference to Jerusalem, the city founded by David which became the capital of Israel (2 Samuel 5:7–10). Scripture indicates that the Messiah, or the "Anointed One" (Daniel 9:25) would assume the throne of Israel and eventually the world (Psalm 47:2; Isaiah 9:7). Complete fulfillment of this prophecy will happen when Jesus returns to take His throne on earth (Revelation 19:11–15).