Ambrose of Milan — as excerpted in the Catena Aurea on Luke 5:12-16

“He says then, I will, for Photinus, He commands, for Arius, He touches, for Manichæus. But there is nothing intervening between God’s work and His command, that we may see in the inclination of the healer the power of the work. Hence it follows, And immediately the leprosy departed from him. But lest leprosy should become rife among us, let each avoid boasting after the example of our Lord’s humility. For it follows, And he commanded him that he should tell it to no one, that in truth he might teach us that our good deeds are not to be made public, but to be rather concealed, that we should abstain not only from gaining money, but even favour. Or perhaps the cause of His commanding silence was that He thought those to be preferred, who had rather believed of their own accord than from the hope of benefit.”