Mateo 9:27

And when Jesus departed thence
From the house of Jairus, to another in the same city;

two blind men followed him:
very closely, by the direction of others, having heard of the miracle just now performed by him; and from thence concluded he was able to restore them to their sight;

crying and saying,
with great faith and fervour, with much importunity, and frequently repeating the following words,

thou son of David, have mercy on us.
Whence it appears, that they firmly believed, and were fully persuaded, that he was the true Messiah; for "the son of David" was a known character of the Messiah among the Jews: nothing was more common than to call him by this title, without any other additional epithet, (See Gill on Matthew 1:1), and since it had been prophesied of the Messiah, that he should "open the eyes of the blind", ( Isaiah 35:5 Isaiah 42:7 ) they might be greatly encouraged to hope and believe they should obtain mercy from him in this respect.