Luke 20:41–44 (ESV)
Son Is the Christ?
41 But he said to them, “How can they say that the Christ is David’s son? 42 For David himself says in the Book of Psalms,
“ ‘The Lord said
to my Lord,
“Sit at my right hand,
43 until I make your enemies your footstool.” ’
thus calls him Lord, so how is he his son?”
Only the incarnation can answer Jesus’ question. He is both man, David’s son, and God, David’s Lord. Reason
dare not reduce the truths of Scripture. David’s son has become our Lord through His death and resurrection, and the Father has exalted Jesus to His right hand.
“Hail him, ye heirs of David’s line, Whom David Lord did call, The God incarnate, man divine, And crown Him Lord of all.” Amen. (LSB 549:4)
Edward A. Engelbrecht, The Lutheran Study Bible
(St. Louis, MO: Concordia Publishing House, 2009), 1760.