The running position is that the Bible does not talk about homosexuality, or that somehow those passages do not apply, and we cannot tell others how to live in this area. In 50 years we will look back and be ashamed that we had said, "We are very much supportive of the family -- the biblical definition of the family unit" because that sentiment is left to old guys who make great chicken.
We (and I am speaking to Christians at this point) fear, for sake of offending, calling sin, 'sin.' This fear is justified. The church is notoriously bad at finding a pet sin and responding really badly to that. If I were gay, I would fear the church. The immorality of not loving our fellow man is absolutely the same as being black 60 years ago and for that the church in general should be ashamed.
If you are reading this and you are gay, then the message I would want you to know is that you deserve to be loved by your fellow man (something Christians have failed at a lot), and the message of the Bible is that you are deeply loved by God, just as you are. His desire is to reveal himself to you and to engage in a relationship with you. If that is intriguing, pick up a Bible. Try starting with the book of John. There are churches where you are welcome.
The rest of this is a theological exercise which is small and unimportant in comparison to that greater truth.
To my fellow Christians, I would propose that this issue of calling sin, 'sin' is of higher importance than we put it. The ability to simply dismiss a Christian tenant because its no longer popular with our culture is dangerous. Being jerks to people we disagree with is just as dangerous and needs to be addressed (just not in this post.)
There are a few key theological premises in order to continue:
Scripture is authoritative.
Scripture has the ability to define boundaries to our actions that we are then obligated to follow as Christians.
The first is critical, because for many, the idea that scripture is authoritative has fallen out of vogue. We run to our "Spirit lead" thoughts for our basis of morality. We ended up with many Christians on either side of the pendulum. One side worshiping scripture in place of God, and the other listening only to their own sinful minds attempting to discern the "will of the Spirit." There must be an authoritative foundation on which to build our beliefs and to test the ideas we come up with. That foundation is Scripture. Scripture needs to have been given to us by God, and the contents of it (including Paul's writings) need to be authoritative. Without that, there is no basis for this discussion. You are free to think whatever your heart tells you is right. I don't trust my heart that much.
The second question should be obvious as well, however, there are those who accept the idea of the Bible as an old and outdated book that has no practical meaning to our lives. If that is true, then there is also no basis for the discussion.
Assuming then that in order to have this discussion there must be an agreement that scripture is authoritative and can set moral boundaries (to which crossing them is sin), that leads us to the question of what "sins" are sins, and specifically is homosexuality one of them.
If you really want all the verses, a google search can provide a plethora of verses on the Bible and homosexuality, but I would focus primarily on this passage:
Romans 1:18-32There is so much here to unpack as we see a clear progression.
18 For the wrath of God is revealed from heaven against all ungodliness and unrighteousness of men, who by their unrighteousness suppress the truth. 19 For what can be known about God is plain to them, because God has shown it to them. 20 For his invisible attributes, namely, his eternal power and divine nature, have been clearly perceived, ever since the creation of the world,[g] in the things that have been made. So they are without excuse. 21 For although they knew God, they did not honor him as God or give thanks to him, but they became futile in their thinking, and their foolish hearts were darkened. 22 Claiming to be wise, they became fools, 23 and exchanged the glory of the immortal God for images resembling mortal man and birds and animals and creeping things.24 Therefore God gave them up in the lusts of their hearts to impurity, to the dishonoring of their bodies among themselves, 25 because they exchanged the truth about God for a lie and worshiped and served the creature rather than the Creator, who is blessed forever! Amen.26 For this reason God gave them up to dishonorable passions. For their women exchanged natural relations for those that are contrary to nature; 27 and the men likewise gave up natural relations with women and were consumed with passion for one another, men committing shameless acts with men and receiving in themselves the due penalty for their error.28 And since they did not see fit to acknowledge God, God gave them up to a debased mind to do what ought not to be done. 29 They were filled with all manner of unrighteousness, evil, covetousness, malice. They are full of envy, murder, strife, deceit, maliciousness. They are gossips, 30 slanderers, haters of God, insolent, haughty, boastful, inventors of evil, disobedient to parents, 31 foolish, faithless, heartless, ruthless. 32 Though they know God's righteous decree that those who practice such things deserve to die, they not only do them but give approval to those who practice them.
God gives truth. Man is unrighteous and therefore suppresses the truth. The truth is plainly obvious, but by not honoring God, they become self focused in their thoughts, and in what they worship. God gives them up to their natural sinful bents (one of which is homosexuality). After so much time, they lose sight of the moral framework God established so much that they start giving approval to those who practice immorality.
There is not a single integrous reading of this scripture that does not take homosexuality and place it into a list of sinful practices that is against God's revealed plan for morality. There is no way around it. However! there is also no way around reading this passage and somehow placing homosexuality as some higher form of sin than any other. Gossips, slanderers, boastful, heartless, ruthless. These characteristics are equated to the same state of debased mindset as homosexuality. We cannot therefore treat homosexuality differently than any other sin* without having that be simply our cultural lenses distorting our view of sin. All sins are equal.
For way too long, we have allowed certain sins to be acceptable, while others are absolutely unacceptable in any form.
Let me illustrate with an example. I knew a guy once who was a liar. He was deceitful all the time to the point where people defined him as such. He was so comfortable with lying that he did so even when it made no sense to. He taught a Sunday school class. If a gay couple walked into their church it would be a total uproar, but this guy was fine. His sins were acceptable. Theirs was not. Both are wrong.
Sin is sin is sin. We all deal with sin issues in our lives. A Christian recognizes they are sinning and allows the Holy Spirit to convict them, asks forgiveness, and attempts to change the immoral behavior. But when a Christian moves from "I am struggling with this sin" to living freely and openly in that sin, then something has happened. That difference is described in verse 24, 26, and 28 as God giving them up to their sinful desires. At that point, the person is living in unrepentant sin. Does not matter if that sin is pride, strife, gossip, or homosexuality.
The reaction from other Christians should be the same.
So in order to understand how we should react to a gay person we should use a little golden rule tactic. Pick the sin you are most comfortable with from the list above. For me its envy. I struggle with a fair share of envy, so I can relate. Then ask the following questions:
Can a person be born with a natural bent toward envy?
If a person tells me they struggle with envy, would I feel a visceral reaction to them? How would I respond? Should I love them or hate them.
If I see that a person is envious, should I be disgusted by them, or love them in spite of their sin?
Would a person who is envious visiting my church for the first time feel welcome?
If it was obvious that the person had a serious problem with envy, would we let them serve as leaders?
Now, switch all the envy's to homosexualilty and while I will not tell you how to answer these questions, I can only say your answers must match.
You see, its time to stop picking and choosing our sins, and to get serious about holiness across the board. That means removing the cultural stigmas of certain sins while getting serious about the lesser sins that we allow to grow in our hearts because we think they are no big deal.
* There is one caveat that sexual sin differs from other sin in that it directly involves the defiling of the Holy Spirit's temple (I Cor 6:18) but this would mean that homosexuality is a sexual sin akin to fornication or pornography, etc.