Matthew 21:29

He answers haughtily, I will not. But when, at the coming of the Saviour, the Gentile people, having done penitence, laboured in God's vineyard, and atoned by their labour for the obstinacy of their refusal, this is what is said, But afterward he repented, and went.

For the Gentiles from the beginning leaving God and his righteousness, and going over to idols and sins, seem to make answer in their thoughts, We will not do the righteousness of God.

Whence we may gather, that in this parable the Lord spoke to such as promise little or nothing, but in their works shine forth; and against those who promise great things but do none of these things that they have promised. Notwithstanding, the Jews are not shut out that they should never enter into the kingdom of God; but, when the fulness of the Gentiles shall have entered in, then all Israel shall be saved. (Rom. 11:25.)

After this, He saith, "What think ye? A man had two sons; and he saith to the first, go, work to-day in the vineyard. But he answered and said, I will not: but afterward he repented, and went. And he came to the second, and said likewise. And he answered and said, I go sir: and went not. Whether then of them twain did the will of his father? They say, the first." Again He convicts them by a parable, intimating both their unreasonable obstinacy, and the submissiveness of those who were utterly condemned by them. For these two children declare what came to pass with respect to both the Gentiles and the Jews. For the former not having undertaken to obey, neither having become hearers of the law, showed forth their obedience in their works; and the latter having said, "All that the Lord shall speak, we will do, and will hearken," in their works were disobedient. And for this reason, let me add, that they might not think the law would benefit them, He shows that this self-same thing condemns them, like as Paul also saith, "Not the hearers of the law are just before God, but the doers of the law shall be justified." For this intent, that He might make them even self-condemned, He causes the judgment to be delivered by themselves, like as He does also in the ensuing parable of the vineyard. And that this might be done, He makes trial of the accusation in the person of another. For since they were not willing to confess directly, He by a parable drives them on to what He desired.

This He brings in because the Priests had asked not in order to learn, but to tempt Him. But of the common folk many had believed; and for that reason He brings forward the parable of the two sons, showing them therein that the common sort, who from the first professed secular lives, were better than the Priests who from the first professed the service of God, inasmuch as the people at length turned repentant to God, but the Priests impenitent, never left off to sin against God. And the elder son represents the people; because the people is not for the sake of the Priests, but the Priests are for the sake of the people.