In one of his famous dialogues with the Pharisees Jesus skillfully appealed to creation norms to trump the part of the Mosaic Code that permitted men to divorce their wives for frivolous reasons.
Have you not read that he who created them from the beginning made them male and female, and said, 'Therefore a man shall leave his father and mother and hold fast to his wife, and they shall become one flesh'? So they are no longer two but one flesh. What therefore God has joined together, let no man separate. . . . Because of your hardness of heart Moses allowed you to divorce your wives, but from the beginning it was not so. And I say to you: whoever divorces his wife, except for sexual immorality, and marries another, commits adultery. (Matthew 19:4-6, 8-9)
Here Jesus intertwined the teachings of Genesis 1 and 2 to tie marriage indelibly to the ordering of human beings as male and female, an ordering that was itself indelibly tied to God's purposes for sexuality and procreation. By linking the sexual relationship between male and female introduced in Genesis 1 to the one flesh union introduced in Genesis 2, Jesus pronounced judgment on all legal engineering that would reduce marriage to something else (in the case of Matthew 19, an opportunity for men to treat women like slaves).
It was a powerful argument and one that played no small part in elevating natural law as a fundamental concept in Christian ethics. Calvin used the "hardness of heart" argument to explain numerous parts of the Mosaic Law that he found lacking. The ultimate standard for Christians, he pointed out, is the natural moral law that stems from creation, not the various stipulations of the Torah.
Others have appealed to creation norms to critique slavery, various forms of oppression, sexual immorality and environmental degradation.
Can we appeal to creation to defend same-sex marriage?
And yet here is the rub. Christians have also appealed to nature as justification for racial segregation. Others have used it to defend social patriarchy. Now some are beginning to appeal to creation to defend same-sex marriage.
The question is, how do we determine the moral meaning of creation? How do we determine the content of natural law?
Surely we can rule out a few forms of argument.
1. We should not be gathering ethical norms from the ways in which animals interact. It makes little moral sense to say, "if chimpanzees do it, why can't we?" There are fundamental differences between humans made in the image of God and animals.
2. We should not be slavishly imitating the ways of life of the first human beings. It makes little sense to argue that if Adam and Eve walked everywhere they went, so should we. We can accept the accomplishments of culture and technology.
3. We do not have precisely the same obligations that were given to the first human beings in Genesis 1-2. For example, Genesis says that God rested on the seventh day and declared it to be holy. Deuteronomy 5 presents this as the basis for the sabbath law that was so central to the covenant with Israel. But Paul declares that Christians are no longer bound by a sabbath day (Colossians 2), and even most Christians who believe in a new covenant sabbath emphasize that it no longer falls, as it did at creation, on the seventh day of the week.
4. This last point is very important. Christ has fulfilled the purposes of creation, and it is in him that we now seek our own participation in that fulfillment. Christian ethics does not look backward — as if the goal were to try to get back to creation — but forward, toward the fulfillment of creation in Christ.
Is the natural law relevant?
But does that mean that creation, or the natural law, is no longer relevant?
Jesus' teaching regarding the nature of marriage, like Paul's various appeals to creation, remind us that the order of creation remains, even though it must now be interpreted in light of the work of Christ. So the task at hand, when wrestling with matters like human dignity as grounded in the image of God, the call to be fruitful and multiply, the call to work, the command to exercise dominion, the institution of marriage, and the meaning of gender, is to determine how we fulfill the purposes of creation in light of what Christ has done and is doing.
Yet this can be tricky. For, how do we tell the difference between the sort of fulfillment that entails the transcendence of a certain dimension of the creation order (i.e., the sabbath day) even as it continues to be fulfilled in more meaningful ways (i.e., resting in Christ, worshiping God, etc.), and claims about fulfillment that amount rather to a contradiction or nullification of the creation order?
These latter claims can take various forms, but they invariably embrace dimensions of the fall into sin and integrate those dimensions into a new, corrupted understanding of creation. Is this not what we see in forms of patriarchy that exploit women, defenses of social systems that idolize racial segregation, and visions of cultural progress that run roughshod over the environment?
Christians wrestling with whether or not God is calling us to affirm homosexual relationships within the church need to work through these basic questions.
Does it transcend or distort the created purpose?
It is one thing to say that the work of Christ points us to the fulfillment and transcendence of marriage, procreation, and gender, a logic that leads to a new appreciation for the significance of celibacy within the Christian tradition (1 Corinthians 7). After all, Jesus himself said that in the kingdom there will be no marriage (Luke 20). Those who choose to be celibate therefore anticipate the fulfillment of creation's own purposes. Those who devote themselves to bonds of love that transcend sexuality anticipate the future communion of all in God.
It is another thing entirely to say, as some are saying, that we may therefore do with marriage, sexuality, and gender whatever we desire. To engage in sexual intercourse without a willingness to accept the children God may provide (if our birth control fails, for instance) is to turn a basic purpose of sexuality on its head. Do we not do the same when we seek sexual gratification through practices fundamentally different from what sex actually is and was intended to accomplish according to the design of creation? This is not transcendence or anticipation of future fulfillment, but distortion of created purpose. It does not direct people to the renewal of creation in the coming kingdom of God. It drives them back to the hopelessness of corrupted and fallen creation.
It is true that in Christ there is no male or female, just as there is neither Jew nor Greek, neither slave nor free (Galatians 3). But this points us to the transcendence of sexuality in the communion of Christ, not to its distortion. Because we still live in that time between the two ages, inhabiting the tension between the already and the not-yet, we can anticipate that communion only by forming bonds of love while abstaining from sexual activity or by entering marriages oriented toward the purposes of the created order that nevertheless reflect the love between Christ and his church.