27 When Jesus departed from there, two blind men followed Him, crying out and saying, “Son of David, have mercy on us!”
28 And when He had come into the house, the blind men came to Him. And Jesus said to them, “Do you believe that I am able to do this?” They said to Him, “Yes, Lord.”
29 Then He touched their eyes, saying, “According to your faith let it be to you.”
30 And their eyes were opened. And Jesus sternly warned them, saying, “See that no one knows it.”
31 But when they had departed, they spread the news about Him in all that country.
This account only appears in Matthew.
Son of David (v.27) — Son of David is His title as He stands in relation to His earthly people, and in this passage we have Him called by this name for the first time in the Gospel. The cry these two men utter is specifically Jewish, and surely no Gentile will cry to Him as Son of David. later in the Gospel a Gentile woman cried after Him, “Have mercy on my, Lord, son of David; my daughter is miserably possessed by a demon. But He did not answer her a word” (Matthew 15:23). When she called again, she said, “Lord, help me,” and after she had taken her place with the dogs the Lord acknowledged her faith. — Gaebelein, pages 197-198.
Since “Son of David” was a messianic title, these men were revealing that they had heard Christ’s presentation of Himself as Messiah and were appealing to Him for a messianic miracle. Although Christ, in ministering to the needs of people, sometimes performed miracles when faith apparently was absent (cf. Luke 22:51), in responding to a request for a messianic miracle, He demanded faith. Thus Christ asked them, “Do you believe that I am able to do this?” (v.28), and they confessed, “Yes, Lord.” Again they addressed Him with the messianic title of “Lord” (cf. Psalm 110:1). In response to their faith, the petition was granted and Christ removed their blindness. — Pentecost, pages 225-226.
See that no one knows it (v.30) — The leaders of the nation had already indicated their determination to reject Christ; and so He commanded these blind men, “See that no one knows about this” (Matthew 9:30). Christ had previously said that He had no further evidence to give this nation apart from the sign of Jonah (12:39). Thus Christ did not intend that these men become witnesses to the nation. — Pentecost, page 226.