Kim Paffenroth, «Jesus as Anointed and Healing Son of David in the Gospel of Matthew», Vol. 80 (1999) 547-554
Matthew handles his material in order to relate Jesus anointing, healing, and his title "Son of David". Matthew does this in order to present Jesus as the uniquely anointed "Christ", the Son of David who has come to heal, and who is in that respect (and others), greater than his father David.
Jesus is twice acclaimed Son of David as he practices his final, climactic healing ministry within the temple37. In particular, he is said to heal "the blind and the lame" in the temple (Matt 21,14). When David conquered Jerusalem, he mockingly called his enemies "the lame and the blind": "David had said on that day, Whoever would strike down the Jebusites, let him get up the water shaft to attack the lame and the blind, those whom David hates. Therefore it is said, The blind and the lame shall not come into the house" (2 Sam 5,8). The Son of David as healer is contrasted, not compared, with his father David: David was a powerful warrior who killed the figuratively blind and lame and excluded them from his "house"; his son Jesus is a powerful healer who cures the literally blind and lame within his "house", the temple38.
Similarly, in the last pericope dealing with Jesus status as Son of David (Matt 22,41-46)39, Jesus explains that the Christ is the Son of David, but that David calls him "Lord". David is made to acknowledge here what was already implied by having Jesus heal as the Son of David: Davids son is greater than he. This would clearly seem to fit in Matthews portrayal of Jesus as surpassing Davidic persons and institutions40: Jesus is also greater than the temple (Matt 12,6 unique to Matthew) and greater than Solomon (Matt 12,42 // Luke 11,31). In Jesus healings, he is shown to be greater than his father David, who could not heal in a similar situation that also included the motifs of fasting and anointing mentioned above: "David therefore pleaded with God for the child; David fasted, and went in and laid all night on the ground.... On the seventh day the child died" (2 Sam 12,16, 18)41. Jesus, the Son of David, can do what his father could not, save his dying children, both within and outside Israel42.
In all of this Matthew does not overturn or reject the title Son of David for Jesus: in light of the first verse of Matthews Gospel, it would seem to be an incredible claim to say that he does43. Matthew embraces the title, then expands its implications to include the compassionate power shown in Jesus healings. It is not that Matthew shows Jesus to be more than the Son of David, but instead that Matthew shows Jesus to be the Son of David who is more than David. Matthew depicts Jesus as the Christ, the uniquely anointed Son of David, who is uniquely capable of healing.