John Piper preached a sermon on Sunday, June 16, 2012, with the title, “Let Marriage Be Held in Honor” — Thinking Biblically About So-Called Same-Sex Marriage.” In light of the proposed Marriage Amendment coming before Minnesotans this fall (“Shall the Minnesota Constitution be amended to provide that only a union of one man and one woman shall be valid or recognized as a marriage in Minnesota?”), Piper gave a biblical vision of marriage (constructive theology) in relation to homosexuality (polemical theology).

Piper’s introduction:

Today’s message is built around eight points designed to give a biblical vision of marriage in relation to homosexuality, and in relation to the proposed Marriage Amendment in Minnesota. I asked that Hebrews 13:1–6 be read not because I will give an exposition of it, but to highlight that one phrase in verse 4: “Let marriage be held in honor among all.” That is what I hope to advance, for the glory God and for your guidance and your good.

Here are the eight points Piper laid out and expanded upon in the sermon. In numbers 7 and 8 Piper spells out the impact of these previous doctrinal truths (1-6) on how we ought to think about polices and laws and engaging in that debate as Christians. I include an extended excerpt from his sermon under these two points.

1. Marriage is created and defined by God in the Scriptures as the sexual and covenantal union of a man and a woman in life-long allegiance to each other alone, as husband and wife, with a view to displaying Christ’s covenant relationship to His blood-bought church. [Piper focused on four key texts: Genesis 1:27-28; Genesis 2:23-24; Matthew 19:4-6; Ephesians 5:24-32.]

2. There is no such thing as so-called same-sex marriage, and it would be wise not to call it that.

3. Same sex desires and same sex orientation are part of our broken and disordered sexuality owing to God’s subjection of the created order to futility because of man’s sin.

4. Therefore, same-sex intercourse, not same-sex desire is the focus of Paul’s condemnation when he threatens exclusion from the kingdom of God.

5. Therefore, it would contradict love and contradict the gospel of Jesus to approve homosexual practice, whether by silence, or by endorsing so-called same-sex marriage, or by affirming the Christian ordination of practicing homosexuals.

6. The good news of Jesus is that God saves heterosexual sinners and homosexual sinners who trust Jesus, by counting them righteous because of Christ, and by helping them through His Spirit to live lives pleasing to Him in their disordered brokenness.

7. Deciding what actions will be made legal or illegal through civil law is a moral activity aiming at the public good and informed by the worldview of each participant.

How should Christian citizens decide which of their views they should seek to put into law? Which moral convictions should Christians seek to pass as legal requirements? Christians believe it is immoral to covet and to steal. But we seek to pass laws against stealing, not against coveting. One of the principles at work here seems to be: the line connecting coveting with damage to the public good is not clear enough. No doubt there is such a connection. God can see it and the public good would, we believe, be greatly enhanced if covetousness were overcome. But finite humans can’t see it clearly enough to regulate coveting with laws and penalties. This is why we have to leave hundreds of immoral acts for Jesus to sort out when He comes.

Laws exist to preserve and enhance the public good. Which means that all laws are based on some conception of what is good for us. Which means that all legislation and all voting is a moral activity. It is based on choices about what is good for the public. And those choices are always informed by a world view. And in that worldview — whether conscious or not — there are views of ultimate reality that determine what a person thinks the public good is.

Which means that all legislation is the legislation of morality. Someone’s view of what is good — what is moral — wins the minds of the majority and carries the day. The question is: Which actions hurt the common good or enhance the common good so much that the one should be prohibited by law and the other should be required by law?

Here are a few thoughts to help you with that question:

1. A constitutional amendment should address a matter of very significant consequence. To give you an idea of what has been regarded as worthy inclusion in the state constitution, Section 12 of Article xiii was passed by voters in 1998. It reads as follows: “Hunting and fishing and the taking of game and fish are a valued part of our heritage that shall be forever preserved for the people and shall be managed by law and regulation for the public good.” In deciding whether the meaning of marriage is significant enough to put in the constitution one measure would be to weigh it against hunting and fishing.
2. The recognition of so-called same-sex marriage would be a clear social statement that motherhood or fatherhood or both are negligible in the public good of raising children. Two men adopting children cannot provide motherhood. And two women adopting children cannot provide fatherhood. But God ordained from the beginning that children grow up with a mother and a father, and said, “Honor your father and your mother” (Exodus 20:12). Tragedies in life often make that impossible. But taking actions to make that tragedy normal may be worth prohibiting by law. That's a factor to consider.
3. Marriage is the most fundamental institution among humans. It’s origin is in the mind of God, and its beginning was at the beginning of the creation of humankind. It’s connections with all other parts of society are innumerable. Pretending that it can exist between people of the same sex will send ripple effects of dysfunction and destruction in every direction, most of which are now unforeseen. And many of those that are foreseen are tragic, especially for children, who will then produce a society we cannot now imagine.
4. Before now, as far as we know, no society in the history of the world has ever defined marriage as between people of the same sex. It is a mind-boggling innovation with no precedent to guide us, except the knowledge that unrighteousness destroys nations, and the celebration of it hastens the demise. (Deuteronomy 9:5; Proverbs 13:34; Romans 1:24–32)

8. Don’t press the organization of the church or her pastors into political activism. Pray that the church and her ministers would feed the flock of God with the word of God centered on the gospel of Christ crucified and risen. Expect from your shepherds not that they would rally you behind political candidates or legislative initiatives, but they would point you over and over again to God and to His word, and to the cross.

Please try to understand this: When I warn against the politicizing of the church, I do so not to diminish her power but to increase it. The impact of the church for the glory of Christ and the good of the world does not increase when she shifts her priorities from the worship of God and the winning of souls and the nurturing of faith and raising up of new generations of disciples.

If the whole counsel of God is preached with power week in and week out, Christians who are citizens of heaven and citizens of this democratic order will be energized as they ought to speak and act for the common good.