Matthew 9:12

What then saith Infinite Wisdom? "They that be whole need not a physician," saith He, "but they that are sick." See how He turned their reasoning to the opposite conclusion. That is, while they made it a charge against Him that He was in company with these men: He on the contrary saith, that His not being with them would be unworthy of Him, and of His love of man; and that to amend such persons is not only blameless, but excellent, and necessary, and deserving of all sorts of praise. After this, that He might not seem to put them that were bidden to shame, by saying, "they that are sick;" see how He makes up for it again, by reproving the others.

Luke adds to repentance, which explains the sense; that none should suppose that sinners are loved by Christ because they are sinners; and this comparison of the sick shows what God means by calling sinners, as a physician does the sick to be saved from their iniquity as from a sickness: which is done by penitence.

He calls Himself a physician, because by a wonderful kind of medicine He was wounded for our iniquities that He might heal the wound of our sin. By the whole, He means those who seeking to establish their own righteousness have not submitted to the true righteousness of God. By the sick, He means those who, tied by the consciousness of their frailty, and seeing that they are not justified by the Law, submit themselves in penitence to the grace of God.

For they do not come to Jesus while they remain in their original condition of sin, as the Pharisees and Scribes complain, but in penitence, as what follows proves; But Jesus hearing said, They that be whole need not a physician, but they that are sick.