John Calvin on Matthew 9:29

29. According to your faith. Though the subject of the narrative is a remarkable benefit conferred on two blind men, yet from this declaration of Christ we may draw the general doctrine, that if we pray in faith, we will never sustain a refusal in our prayers. But if those two men, whose faith was small and imperfectly formed, obtained what they wished, much more efficacious will now be the faith of those who, endued with the Spirit of adoption, and relying on the sacrifice of Christ, shah approach to God.