Lets start by looking at the context. Matthew 18 is the fourth major discourse of Jesus in the book. It seems to follow the theme of Instructions for the Believing Community, and could be titled: Living Together: The Discourse on Relationships.
The major points of Mt. 18 seem to be: Dont be the kind of person who offends others so much so that they stumble away from the kingdom of God. Instead, work out the offenses and live in peace with each other, forgiving when others have offended you. It goes both ways. Special attention is devoted to the strains and tensions caused by people who only live by self-concern and lack of care for other believers, through bad examples and bad behavior, and through an unwillingness to forgive as we have been forgiven. A disciples interests, values, outlooks, goals, and so on must match those of God in heaven. We must be willing to die to ourselves for the sake of being a servant of God. Humility is a recurrent theme.
The teaching of 18.15-20 is to emphasize restoration and the primacy of forgiveness. There must be a correspondence between heaven and earth in all things. It is the job of a disciple to see to it that he does as God does, that the will of the Father is carried out on this earth. It is not that God needs to concur with our conclusions, but that we need to live in accordance with his will.
On to the question of 18.21: How many times should I forgive? Jesus answer is clear: There is no limit. A parable of forgiveness follows, but its interesting to observe that forgiveness is limitless until the debtor misbehaves, then forgiveness is completely withdrawn. Again, his punishment was not on the basis of his debt, but on his unforgiving behavior. So forgiveness does have its limits, but the point of the parable is that we should forgive as we have been forgiven.
Following this context, interestingly enough, we roll into Matthew 19. We see right away that the Dt. 24 text rises its head, and the question (a trap) about divorce for any and every reason. They are testing him with a situation where every answer could mean trouble for Jesus. They really couldnt care less about the divorce question; theyre just trying to trap the man they despise. Their question is not sincere, and they are not honestly seeking information about divorce. Divorce was allowed in Jewish culture. The difference of opinion, that sets up the trap, was centered in the grounds for divorce.
Already we also see the antithesis to the principle laid down in 18.10-14. The Pharisees, by their loose approach to divorce, are example of those whose interests and concerns do not match those of God in heaven. They are asking a question about legal technicalities and miss the point of marriage: the union of two people for eternity, which is where Jesus immediately takes them.
In 19.4, Jesus pointed out the difference between Gods plan for marriage and the human institution of marriage. Yes, Jesus recognized that the spiritual institution of marriage is quite distinct from the legal institution of it, even though the legal institution of marriage is directly ordained by God. The legal institution of marriage accommodates sinful mans faults; the spiritual institution transcends them and aims for the highest ideals in marriage. Further, the legal institution of marriage cannot be soft-pedaled on the grounds that Moses law instituted the bare minimum necessary to ensure morality, whereas the spiritual institution goes further and dispenses grace. In Jesus view, there unquestionably was an important distinction between the legal and spiritual institutions of marriage.
As usual, Jesus conversations with the Pharisees are about the Law, because in their minds, Law is all. This one is no different. They came to Jesus with Lets fight about the Law, and well trap you for sure. Jesus responds with, The spiritual institution of marriage follows Gods ideal of a permanent, unbreakable union; the legal institution of marriage gives allowances for divorce to accommodate mans sinfulness, though there have to be justifiable grounds for such action. He left them standing with their mouths gaping openhe didnt fall into their trap.
Back to our context. As I already said, disciples interests, values, outlooks, goals, and so on must match those of God in heaven. Our lives are to be characterized by humility, self-denial, concern for others, and forgiveness. Can you see how Jesus answers flow right into what he has been teaching the people, and primarily, his disciples? This trap provides him an excellent illustration to keep teaching them all about godly relationships.
Verse 6: It is interesting that the commentators (Robertson, Vincent, and Richards) agree that Therefore what God has joined together let man not separate refers to the permanence of the institution of marriage, not to individual marriage relationships.
In v. 7 they dive back into Dt. 24, certain that theyve caught him in their trap. Ha! Why, then, does Moses allow divorce? Again, Jesus is not trying to give the ultimate teaching about divorce, but is using their questions, as he always does, to try to draw them to God and enlighten them about spiritual truth. Moses never commanded that, boys, but he allowed it. There is a difference between the spiritual institution and the legal realities. Our legal system does the same thing when it allows for 2nd degree murder, involuntary manslaughter, or not guilty by means of insanity. The point is not to make divorce acceptable, but to always insist on just cause, to limit sinfulness as much as possible, and to control the consequences of sin to keep it in check. Marriage and divorce were being abused in their day, and Jesus spoke against it. It was a situation of callous and common moral perversity. Jesus judgment presupposes the abiding validity and obligation of the original spiritual institution of marriage, but also to recognize that on earth it doesnt always work the way it should. And God authorized that which was less than ideal.
Lets not misunderstand. Jesus does not say that God in any way had lowered his ideal. Jesus did not say that divorce and remarriage are right. In fact, in going back before Law to the Creation Jesus demonstrated conclusively that divorce and remarriage have never been right! But God still permitted divorce! God allowed the certificate of divorce to be drawn up, witnessed, and presented to a spouse. It was God who spoke of the individuals remarriage after the divorce. It was God who gave the sin of divorce and remarriage its social legitimacy. God understood that in a sin-tainted human society, many men and women would not follow the path to greatness, and that for some the hurt would be too great to bear.
Jesus statement about mans hardness of heart is not a statement of condemnation. It is a statement of compassion and mercy. Knowing our need, God showed himself willing to meet us in the reality of our lives, coming to us with grace. He did not demand that we meet him only in that storied and desirable land of the ideal.
When one takes away the rules, however, too often things fall into chaos very quickly. Once you say, Oh, its just not black and white, you might as well open Pandoras box, right? Its important to never lose sight of the ideal while we live our lives in an atmosphere of grace.
In Matthew 19.9, we have the much fought over exception clause: except for unfaithfulness. Im going to have to stick with my interpretation of this word from Matthew 5.31-32, since its exactly the same word (porneias). I know I am going against the flow of the traditional interpretation of this text, but Im convinced about 5.31-32, so Ill stick to my guns here on the grounds that (1) Jesus is self-consistent, (2) he is answering the same question about divorce that he answered in Mt. 5.31-32, and (3) he is commenting on the same text form Deuteronomy 24.1-4 that he commented on in Mt. 5.31-32. Remarriage is forbidden after an illegitimate divorce based on invalid cause. But if the divorce is valid, then remarriage must be acceptable, just as it was in commonplace Jewish custom.
Lets not fool ourselves, though. Jesus is taking a hard line here against divorcea very conservative stance. The creation ordinance matters, and it matters a lot. But its not the final word.
Have I been fair?