John Calvin Commentary Matthew 9:28

"And when he was come into the house, the blind men came to him: and Jesus saith unto them, Believe ye that I am able to do this? They say unto him, Yea, Lord." — Matthew 9:28 (ASV)

Do you believe that I can do this? But from other passages of Scripture, it is evident that our knowledge of his power will be cold and unprofitable if we are not convinced of his willingness. And yet Christ is satisfied with their reply and praises their faith, as if it had been all that could be wished.

I answer, they had some perception of his grace, for they had already acknowledged him to be the Son of David, bestowing on him this title as Redeemer of their nation and author of all blessings.

He therefore interrogates them concerning his power and further inquires if they believe earnestly.

Faith embraces the mercy and fatherly love of God along with his power, and the generous design of Christ along with his ability to save.

But since people commonly ascribe less than they should to the power of God and the ability of Christ, there was good reason for asking this question of the blind men: if they believe that Christ can do what they have professed with their mouths.

Indeed, Christ simply wished to know if they were sincere in giving him the honor of Messiah. Therefore, he praises their faith because, despite that humble and contemptible appearance, they acknowledged him to be the Son of David.