When considering any complicated topic, there are a few different ways I approach it as I try to form my own opinion. In general, I can usually sum up my approaches as:
1) Science/empirical knowledge
3) Personal experience
Where's the bible in this, you might ask? My perception of scripture heavily influences how I look at all three areas above! The text is so rich and so layered that I certainly include it in almost every major decision I make. But you've seen on this blog how I can dive into a passage of scripture and tie myself in knots with in-depth study!
Besides, on this topic (is homosexuality a choice) the bible is silent. So the three points above are what I've used to think about this, and all three approaches lead me to the same opinion.
Quick note before I begin: what I'm talking about here is homosexuality, the sexual and romantic attraction to people of the same sex. I'm not talking about homosexual behavior.
#1 -- Science
This one was pretty easy for me because the studies have been out there for quite a while. I won't cite them or link to them since they're readily available on the internet if you're interested, but there are two that quickly come to mind.
The first is at least 20 years old and was the result of scientists' efforts to better understand fetal development in the womb. Their discovery was that fetuses receive large rushes of hormones from the mother at different points in their development, and the amount of hormones greatly affects the growing fetus. In males, you can even recognize these effects by looking at finger lengths -- if the ring finger is significantly longer than the index finger, then he likely received a large rush of prenatal testosterone. And he's also more likely to be heterosexual. Less testosterone, his fingers are closer in length, and he's more likely to be gay. Sounds like an urban legend but the data supports it.
The second study is on brain anatomy and function. Hypothalamus size has shown to be correlated to sexual preference, and neuroscientists also discovered that gay people use their brains differently when given a mental task. Real-time MRI technology continues to show amazing things every year, and right now it looks clear that homosexual people have brains that look different and work differently from heterosexual brains.
If it's biological, it's not a choice.
#2 -- Logic
Our society has come a long way in dealing with people who used to be seen as "the least of these". Women's rights, minorities' rights, the end of child labor, and on and on... I'm very grateful to live in a country that continues to make a sincere effort to live up to the ideals of our founding fathers (equality and liberty).
But I say with sadness that it is still very difficult to be gay in America. Especially in some areas of the country. The South is notorious for this, and having lived most of my life in the South I can affirm that the reputation has been earned.
I've seen children mocked and brutalized for their sexuality. I've seen teens disowned by their families because they wouldn't "turn straight". I've seen adults cowering in fear that someone might find out about the secret they've been holding inside, terrified, for decades. (See here for a powerful video on this topic).
Who would choose that?
C.S. Lewis used this logic as proof that Jesus' resurrection was real -- he noted that only insane people would give up their lives for a blatant lie, and the disciples were all willing to give up their lives to spread the news of the resurrection. And they weren't insane.
Gay kids are giving up their lives every week in this country. Would they do that if they were faking it, or just to cause trouble?
#3 -- Personal experience
Lab results and news stories are all fine, but sometimes to really dive into a topic you need to put a face to it. A soul to it. You need a friend who is in the middle of the topic, living it.
I have gay friends. Some are single and still searching for a true love; others are partnered and hoping to have the legal right to marry one day. I can't think of any friends who are in a gay marriage, but I do have gay male friends who are currently married to women and are working through this massive challenge.
If they could flip a switch and be sexually attracted to their life partner, and leave behind the temptations to break their vows with men, I'm not sure if they'd do it. Being gay is part of who they are, and to me it's not right to just have them wish it away.
But it brings such turmoil to them on a daily basis. They haven't chosen it, and some of them got married in the hopes that over time the attraction to men would pass. It didn't.
They have faces, and souls, and are some of the most god-loving, respectful men I know. And they didn't choose homosexuality any more than I chose to be attracted to tall brunette women with nice legs and great smiles. My sexual preferences are just part of who I am, and haven't changed since I started becoming aware of them around puberty.
Wrapping it up
You certainly don't have to use my framework of these three approaches to the issue. But if you're starting from scratch and haven't really considered any of this before, you might want to do your own research on the science. You might want to think through the logic of what it means to be homosexual, the price that comes with it, and how Christians should treat them.
And finally, and most important, you might want to be a friend to someone who is gay. God has a way of blowing up our stereotypes and our prejudices one face at a time, and I'm so glad He's done that with me.