I have another question, also. As it was pointed in other articles, I also get erect when thinking about another naked male. Does this mean I'm gay?
People use many different things to identify themselves as a part of a group. We can talk about the nation that we belong to or the nation our ancestors came from. We might group ourselves by our gender -- either male or female. Or, we might group ourselves our economic status -- either rich, poor, or middle class. One of the great things about being a Christian is that the identity of being a Christian overrides everything else. "There is neither Jew nor Greek, there is neither slave nor free, there is neither male nor female; for you are all one in Christ Jesus" (Galatians 3:27).
A recent fad has been to identify people by who they choose to have sex with. Looking through history you will find that people didn't do this in the past. Sure, there were people who had sex with males, females, or both. There were also people who had sex with animals. But what you don't find is people using their choice of sexual partners as an identifier that says who they are. Sex is a behavior, not an identifier. If sex becomes an identifier, then what identity does someone have who chooses not to have sex or can't have sex? "For there are eunuchs who were born thus from their mother's womb, and there are eunuchs who were made eunuchs by men, and there are eunuchs who have made themselves eunuchs for the kingdom of heaven's sake. He who is able to accept it, let him accept it" (Matthew 19:12). It makes you wonder why there aren't groups protesting in the streets for equal rights for eunuchs. Why is only one set of sexual behavior being picked for special treatment?
If homosexuality is truly an identifier, like being of African or European descent, then what identity do we ascribe to babies? I can look at a small child and say, "Oh, what a cute little Irishman!" but we rightly abhor the thought of seeing a baby and saying, "What a cute lesbian!" We understand that children don't have sexual desires until they reach puberty. They don't make sexual choices unless it is forced on them, and we rightly seek to protect them from such things.
Your body desires sex. It is how you were designed. Physically, your body really doesn't care what you have sex with, just so long as you can ejaculate when your seminal vesicles start getting full. Therefore, your body is going to respond to anything that it even remotely thinks is a sexual situation. But you and I aren't animals. We are not like a dog who is willing to relieve himself on anything and everything. Our minds override what our bodies might desire. Just because your penis gets erect, it doesn't mean you have to ejaculate then and there. We control our desires and focus them into proper channels. What makes your penis get erect at any given moment in time doesn't define who you are. It merely is an indication that your body thinks this might be a sexual situation -- and when you are young it is far more often wrong than right.
If erections defined who you are, then what do you do with the boys who get erections every morning at ten o'clock? What is their identity? What about the boys who get erect at the thought of running naked through the woods? Or the boys with the crazy bodies that get erect over some inanimate object? My point is that sexual arousal is something every boy deals with and the reason the arousal is triggered has nothing to do who the boy is, beyond the mere fact that he is a boy with a body that is nuts about wanting to have sex. In other words, the fact that you have erections when you see a naked boy tells me that you are a boy. It has nothing to do with whom you chose to have sex with.
God condemns people having sex outside of marriage, that is called fornication. He also condemns having sex with people who are the same gender as you; we call that homosexuality today. "Do you not know that the unrighteous will not inherit the kingdom of God? Do not be deceived. Neither fornicators, nor idolaters, nor adulterers, nor homosexuals, nor sodomites, nor thieves, nor covetous, nor drunkards, nor revilers, nor extortioners will inherit the kingdom of God" (I Corinthians 6:9-10). These refer to behaviors that are sinful.
It is not limited to just the act. For instance, fornication is wrong, but the sin doesn't start when the guy inserts his penis. Sin is a slippery slope, you start to approach it and before you realize it you've gone farther than you intended. Actions that stimulate a desire for sex outside of marriage is also wrong. This is called lewdness in the Bible. That is why Paul said, "It is good for a man not to touch a woman" (I Corinthians 7:1). By that, he means touching in a sexual way because it will start something that you can't legitimately finish.
But another aspect of sin is that we think about committing sin long before we actually do it. "For from within, out of the heart of men, proceed evil thoughts, adulteries, fornications, murders, thefts, covetousness, wickedness, deceit, lewdness, an evil eye, blasphemy, pride, foolishness. All these evil things come from within and defile a man" (Mark 7:21-23). I'm not talking about temptation. We would never be tempted if something sinful never crossed our mind. I'm talking about thinking about sin in ways that you accept the idea of it, even though you may not have actually done the deed. That is a sin that the Bible calls lust. For example, "But I say to you that whoever looks at a woman to lust for her has already committed adultery with her in his heart" (Matthew 5:28). Jesus is not saying it is wrong to look at a woman and think she is pretty. It becomes wrong when you look at a woman and start imagining what it would be like to have sex with her. The reason is that the things we accept in our minds eventually come out in our behavior.
Therefore, having sex with another guy is sin -- homosexuality. Playing with another guy's body to get him aroused is a sin -- lewdness. Wanting to have sex with another guy is a sin -- lust. But looking at a guy and thinking he is handsome or buff is not a sin. Having your penis go erect because you see someone naked is not a sin. What you described doesn't make you a homosexual.
The homosexual movement wants blur the lines of what is sin because the more people think they might be homosexual, the more people will accept and commit the actual sin of homosexuality. If they can get guys to start thinking they might be homosexual just because their penis goes erect around another guy, then they will start thinking about homosexual acts and may even accept them in their heads, which will eventually lead to doing actual homosexual acts. They want people to identify themselves by their sexual behavior so that people won't condemn their choice of sin or try to talk them out of it. However, your choice of sins does not identify who you are. You can change your choices. "And such were some of you. But you were washed, but you were sanctified, but you were justified in the name of the Lord Jesus and by the Spirit of our God" (I Corinthians 6:11).
Thank you so much for your answer. It was really helpful.