Expectation of a Davidic Messiah was rooted in Israel's royal promises. Jesus does not deny Davidic messiahship but challenges an account of the Messiah that stops there.
The right hand of a king is the position of supreme honor and authority.
Psalm 110:1 distinguishes the LORD from David's 'Lord' while inviting the latter to sit at the LORD's right hand until his enemies are subdued.
The distinction means the passage should not be described as a simple equation of Messiah and YHWH. Its force lies in extraordinary heavenly exaltation beside God.
Jesus asks how the scribes can say that the Christ is David's son, then cites David's Spirit-inspired words calling the Messiah 'my Lord.'
The question remains unanswered in the scene, inviting the reader to understand Jesus as both Davidic Messiah and David's exalted Lord.
This is strong evidence of transcendent messianic identity, especially because Mark will reuse Psalm 110 at Jesus' trial.
The passage preserves distinction between God and the Messiah while placing Jesus in the highest heavenly position beside God.
The large crowd hears Jesus gladly.