One question that commenters often ask in response to any posts on this site regarding marriage, divorce, or adultery, is "why get married at all?" For instance, one recent commenter to an earlier post of mine on adultery wrote:
If I want to "be with" a man and he with me, why can't we just agree to be together and that's that? Why all of the vows, rings, stigma, government involvement and harsh rules? Marriage is a business. It's not about love or emotional connection...it's about feeling like you can rightfully own another person.
In other words (if I may paraphrase), why isn't love enough? Why do people have to make commitments in front of (take your pick) God, the state, family, friends, the community, and so forth?
Commitment, in this sense, has two aspects, one negative and one positive. The one which commenters like the one quoted above criticize is the negative one, which focuses on constraints and rules. That is the "business" or contractual aspect of marriage, the "thou shalt nots" that get us into so much trouble when we decide "yes, we shall."
But there is an important but neglected positive aspect that explains why people voluntarily enter into commitments like marriage: it is way of expressing your love and devotion to another person. Not the only way, of course, but a well-established and particularly declarative way.
And these two aspects of commitment are, to a large extent, inseparable: the public declaration of devotion would not mean as much without the promised made therein. The fact that, in a traditional wedding ceremony, a couple stands up in front of the people who mean the most to them in the world and promise to love each other, support each other, and be true to each other, is what gives that public statement its force. It's also what makes it so heartbreaking, especially to those in attendance at the wedding, when those vows are broken (even if for good reason). And it can be safely assumed that no one would make such promises if not to express to the other person his or her devotion; we rarely make commitments for no reason. Rather, the commitments are the expression of love and devotion.
Now what I imagine happens with many if not most couples is that they start out emphasizing the positive aspect of the marriage commitment, and then over time the focus shifts to the negative. They take their mutual love and devotion for granted as the passion and lust fade, and the rules and constraints take center stage—and these rules and constraints end up seeming all the more binding and unfair in comparison.
This is where the sources of commitment come in. When a couple first declares their love and devotion to each other, and makes that commitment, it comes from their hearts—they want to make those promises voluntarily in expression of their love. In other words, the source of that commitment is internal. Even during the wedding ceremony, I doubt it seems like the priest, rabbi, justice of the peace, or Elvis is shackling the couple with the wedding vows—they want to make them. When the commitment is voluntarily, the positive aspect gets all the emphasis, and the negative hardly seems important. After all, why would I ever want to desert, ignore, or be disloyal to this fantastic person who I'm completely in love with? Perish the thought...
...until later on, when the bloom falls from the rose. Now the promises do not seem so voluntary, the ring seems heavier, and marriage seems more like the list of "thou shalt nots." At this point, commitment seems externally coerced, a institutional legacy of the foolishness of youth that only now made be paid for. This is even more true for marriages that did not start so rosy, that were somewhat contrived of forced by circumstances from the beginning. But even the mostly glorious, romantic marriages can decline over time, and one or both partners may start to resent the promises they once made so freely.
So when partners forget why they said their vows and made their promises in the first place, their meaning is lost, and only the ball and chain remains. One way to avoid this, obviously, is to not forget, to keep the love alive, to celebrate what brought you together in the first place. Then the rules won't seem as important, and the voluntariness of them will almost make them irrelevant—in a sense, the marriage begins anew. (There are many posts by other bloggers here that offer recommendations how to do exactly this.)
But isn't commitment counterproductive? If your partner is forced to be faithful, how can you know he or she is being faithful out of love rather than out of obedience or fear of reprisal? This is another product of the external or contractual view of commitment that emphasizes the constraints over what they express. If indeed your partner must be induced to be faithful, then no, he or she is not truly faithful, and if your partner were truly faithful, the rules and constraints would not matter. So, in a sense, external commitment does reduce its expressive value, that's true.
But... no one is perfect. Few people imagine (or at least admit to themselves) on their wedding day that they will ever be tempted to cheat on their beloved, but we know all too well that many do cheat (and presumably more are tempted). This is exactly where the external view of the marital promise has its value: when human weakness is at play. Even the most devoted partner may be tempted, and he or she may not be strong enough to resist without the commitment (and some aren't strong enough even with it). As the legal philosopher H.L.A. Hart explains in his classic book, The Concept of Law, it is in this way that laws bind even the best of us; when tempted to skirt the law, our respect for the law, if we hold to it internally, may keep us to the straight and narrow.
Basically, if commitments (like marriage) are freely chosen and adhered to, they won't seem like commitments at all, but they will still have all the meaning that commitments ideally have. But when we start thinking of our commitments only as commitments, and lose sight of the reason we made them, then the trouble starts.