Now President Barack Obama has affirmed his support of same-sex marriage. The president's statements should come as no surprise.

His refusal to defend the Defense of Marriage Act and his comments about "evolving" on the issue both pointed toward this event. I Tweeted recently that I expected such a move from the president. The only remote surprise is the timing of his announcement. I, like many others, expected this announcement after he had won a second term in November. This announcement accelerated the timeline of an inevitable conversation.

So how do we as evangelicals respond?

Last year I wrote a brief post on the future of the evangelical response regarding homosexuality after Starbucks' Howard Schultz withdrew from speaking at the Willow Creek Leadership Summit. In that post, I listed five principles to consider about the issue of homosexuality and evangelical churches. Those principles still apply today.

The issue is not going away, and you cannot ignore it or seek to downplay your views. Since Stonewall, the gay rights movement has continued to gain influence. Evangelicals have responded poorly at times and earned a reputation for intolerance. Now, as they seek a more biblical and grace-filled response, we cannot erase our past mistakes. However, we can control our attitudes and responses in the future by being clear and gracious at the same time.

The culture sees this as a "justice" issue -- Christians discriminating on the basis of immutable characteristics.

Christians have always believed and taught that God's standard and intent is a man, a woman, a marriage and a lifetime. To us, that just makes sense, but to an increasing number in our culture, this is simply discrimination. President Obama clearly justifies his reason for supporting gay marriage because of the Golden Rule -- the idea that we should treat others justly, as we would want to be treated.

Though it is easy to make the case in the church that homosexual practice (and marriage) is incompatible with scripture, it will be an exceedingly difficult case to make in today's culture.

I mention in "Subversive Kingdom" an example of running for school board. A half a century ago you would not have been considered for public office in most communities without a strong record of service in and loyalty to a local church. Today that same qualification, if the church teaches biblical truths about homosexuality, is a detriment to one's candidacy in many areas of our country. This will become more of an issue in days to come. Continued...