Now you are the body of Christ, and each one of you is a part of it.
One of the most powerful arguments for the truth, power and reality of the gospel is the unity it brings to people who otherwise would not be united, and in fact might not get along at all, and even worse. This is because our unity is in Jesus Christ, through whom we are brought together into the unity of the Trinity: the Father, the Son and the Holy Spirit.
We are created with differences, and the new creation, as we can see from the passage above (clicking the link shows the immediate context) is just as rich in diversity. Those differences are a good thing. What is challenging for us in this present existence in which we “see through a glass darkly,” and “know in part,” (1 Corinthians 13; KJV) are the many differences we have which we may hold to be nearly first order truths (like the gospel, which is definitely first order), or which we consider important enough to be nonnegotiable. Sexual ethics is a prime example today. Some hold to the orthodox, traditional view of marriage, while others believe in covenant faithfulness in marriage, but believe scripture does not exclude opening up the door to same sex marriage.
First of all, truth is important across the board. I don’t believe in “eternal security,” though many people I know, do. It is important in its place, but as long as we know we have security through faith in Christ, and that we are dependent on God’s gift to us in Christ, and that we are not to live careless lives in this life of grace given to us by God in Jesus, then the question of whether or not one can lose their salvation is rather beside the point to me anyhow. The whole issue becomes just where we draw the lines.
Back to the question on sexual ethics. That’s probably in large part the issue: where we draw the lines and why. The fact of the matter is everyone does so. Not just anything goes for anyone, even if on sexual ethics, it might. We need to make room for some differences, agree to disagree on some things, but somehow still be united in and through Christ and the gospel.
Back to what I consider, more or less gray areas. We can and therefore should live together well with differences of thought concerning the politics of this world. Partly I think, and I would argue that this ought to be the weightiest reason: Jesus is Lord, and Caesar is not. The government of this world still has its place, and is even ordained as well as judged by God. But how that is to be worked out in a given society and era is not something I would consider black and white, even while many issues such as the life of the unborn, and medical care for all, are.
This unity that is ours in Jesus is something we’re to keep working at in this life (Ephesians 4:3). Otherwise, we may well lose it, at least in our witness and testimony to the world. To break away in denial of this unity is a sign that possibly the division is exposing a faith which isn’t genuine. At least it’s an indicator that someone, perhaps both parties in the division, are somehow off track in their following of Christ.
The unity that the gospel brings is not some cookie cutter agreement, but rather a healthy unity which includes differences. But remains steadfast in the oneness of God in Christ, awaiting the time when all that divides us will be gone. And looking for more ways we can agree to live with the differences we have now, while also looking for a unity that is based on a faith which is committed to truth in and through the Truth himself, Jesus (John 14:6).