A day or so after Judge Vaugh Walker struck down California’s marriage amendment in 2010, I was interviewed on Logo TV, the LGBT network. We covered the typical arguments for marriage between one man and one woman cordially, respectfully and predictably. Then I mentioned that from a Christian point of view a central purpose of marriage is to show the love between Christ and his Church — two things that, like a man and a woman, are by nature different. Two men or two women don’t qualify.

The interviewer remained gracious, but, he had been blindsided and the interview was over.

I thought about that a few weeks ago when I had the opportunity to hear theologian Scott Hahn at the World Meeting of Families. Hahn’s lecture, “Back to the Garden of Eden: Unearthing God’s Covenant with Humankind,” traced the theme of marriage from the marriage of Adam and Eve in Genesis to the marriage of Christ and his Church in Revelation.

Hahn emphasized the one-flesh aspect of marriage between those created in the image of God: “So God created humankind in his image, in the image of God he created them; male and female he created them…. Therefore a man leaves his father and his mother and clings to his wife, and they become one flesh” (Genesis 1:27, 2:24).

While every individual is created in the image of God, Hahn said, there is more to it. The image of God is more clearly seen in a matched set — male and female in the covenant of marriage. Then when the matched set procreates, the image comes into even sharper focus. “Molly and me and baby make three” is more than a happy sentiment from an old song. The human family is the image by which we glimpse the Trinity, our God who is a community of persons.

Hahn pointed out that marriage is also an image of the love relationship between God and his people. It’s in the Psalms, the Song of Songs, and the prophets. Jesus likened his second coming to the arrival of a bridegroom (Matthew 25:1-13). St. Paul cited the two becoming one flesh and commented, “This is a great mystery, and I am applying it to Christ and the church” (Ephesians 5:32). “I betrothed you to Christ” he wrote (2 Corinthians 11:2) anticipating the consummated marriage of Christ to his Church (Revelation 19:7-8).

After discussing these themes in his book First Comes Love, Hahn writes, “All this is the word we enflesh in our spousal embrace.”

“Thus,” he continues, “as an image of God, Who is faithful and Who is one, the family bond between husband and wife must be permanent and indissoluble. Thus, too, as God is fruitful and generous, a married couple must be open to life, willing to cooperate with Father in the conception of children.”

Only if we grasp what the Bible says about marriage and the image of God, Hahn writes, can we understand what the Bible and the Church teach about marriage, divorce, fornication, adultery, homosexuality, abortion, contraception, and related topics. Without understanding marriage and the image of God, the inner logic is lost.

To date, we’ve made brilliant and valid natural law arguments that marriage must be between one man and one woman. They have, in large measure, been ignored or rejected.

We’ve made cultural anthropology arguments about marriage as one man and one woman across the world and across time. Nobody really seems to care since we’re all so very modern.

Brilliant New Testament scholars such as Robert Gagnon have effectively debunked gay-friendly interpretations of Romans 1:26-27, 1 Corinthians 6:9, and related texts. And those who don’t like their conclusions go out and find their own “experts” who tell them what they want to hear.

Perhaps it’s time to make the case for marriage as image of the Triune God and of Christ and his Church. At the very least, it would come as a surprise to most Christians, so many of whom are selling out to the culture. It could establish a new conversation about the meaning of marriage in the public debate.

The 2015 Synod on the Family began on Monday. On Sunday, the readings in every Catholic Church worldwide — whether on purpose or by happy providence — included the creation of Eve and her one-flesh marriage to Adam (Genesis 2:18-24) and Jesus’ teaching that marriage is male and female, the two become one flesh, and “what God has united, man must not divide” (Mark 10:2-16).

In this light, the synod will advise the pope about how to better minister to intact and broken marriages and families. In this light, perhaps we can discover a new way to communicate to our troubled culture.