Is the growing acceptance of same-sex marriage reason to despair?

I just scanned through the book Same-Sex Marriage: A Thoughtful Approach to God’s Design for Marriage (Baker) by Sean McDowell and John Stonestreet, which seeks to answer the question: “ ‘What now?’ How can the church best respond in the midst of this changing environment? What will Christian faithfulness look like once new definitions of marriage and sexuality replace those that have undergirded society for so long?” 

The urgency for an answer to the question asked is understandable, for within a span of a little over two decades same-sex unions have gone from unthinkable to commonplace.Scriptures teach that God from the beginning instituted marriage to be a publicly recognized union between one man and one woman for the purpose of procreation (Gen. 1-2). The Word of God can never be broken, but the salt appears to have lost its savor.

One point that McDowell and Stonestreet made that really stuck out is this:

As Christians, we believe that there is something more profoundly true than any and all cultural fads. We believe the kingdom of God, as initiated in the life, death and resurrection of Jesus Christ, is the real story of history. Civilizations come and go. Governments rise and fall. Cultures change and change again. But the kingdom of God has no end.
     We, therefore, refuse to despair. To say or think, “All is lost,” is to say or think something that is not true. As Richard John Neuhaus profoundly put it, “We have not the right to despair, for despair is a sin. And...we have not the reason to despair, quite simply because Christ has risen.”
     That doesn’t mean there’s no cause for concern. There is, and it’s not just what’s “out there” in culture. There’s plenty to be concerned about “in here,” in the Church.

McDowell and Stonestreet also make a very wise qualification: “A closer look reveals that same-sex marriage isn’t causing a radical shift in our understanding of marriage and family; rather, it’s largely the result of one.” Marriage covenants are being broken, and it is less a wonder to see why the entire institution would subsequently become defiled.

The world is really a house built upon shifting sands, and everything within it is in flux. But, there is a house built upon a rock, which is the trusted constant. Whatever is wrong can be made right, and with Christ all things are possible. Marriage, sex, and sexuality can be sanctified, to be what God intended. 

~ WGN