The question of homosexuality is a very touchy topic in this day and age. In our community, it begs the question of if such behavior is sinful. The research I have conducted points to the conclusion that homosexuality is, in fact, a sin.
Before I explain why I have been lead to believe this, I must make a disclaimer. The ideas following this have zero intention to strip these individuals of their humanity or rights, I am just exploring what I have discovered regarding this topic. If I have made an error in judgment of any sort, please point it out so that I may take it into consideration, and either better explain my thoughts or correct my view.
To begin, we will start with one of the very first mentions of homosexuality in the Bible, Leviticus 18 & 20. (There is a mention in Genesis, in the tale of Sodom, but that includes many other issues that become interlined and bring more harm than good in this argument). Leviticus 18:22 states "You shall not lie with a male as with a woman; it is an abomination.", and Leviticus 20:13 states "If a man lies with a male as with a woman, both of them have committed an abomination; they shall surely be put to death; their blood is upon them.". Now, these passages are quite obviously very clear cut in what they state. Despite this, many people have argued that this passage comes from a now irrelevant book of laws, and cannot any longer be applied. However, the only pieces of the Bible that are to no longer be adhered to are those that God and Jesus specifically stated are no longer applicable after our salvation through Him. (i.e. clean/unclean animals in Peter's dream).
However, if the conflict with the book of laws is too much of an issue, there is a verse in the new testament from Paul, which is an even better example.
"Or do you not know that the unrighteous will not inherit the kingdom of God? Do not be deceived: neither the sexually immoral, nor idolaters, nor adulterers, nor men who practice homosexuality, nor thieves, nor the greedy, nor drunkards, nor revilers, nor swindlers will inherit the kingdom of God." - 1 Corinthians 6:9-10. No explanation will help this verse, it's about as clear as it gets. Paul states that God does not condone homosexuality.
Another verse by Paul with the same statement:
The law is not laid down for the just but for the lawless and disobedient, for the ungodly and sinners, for the unholy and profane, for those who strike their fathers and mothers, for murderers, for the sexually immoral, men who practise homosexuality, enslavers, liars, perjurers, and whatever else is contrary to sound doctrine. - 1 Timothy. 1:9-10
I have made my judgment based largely off of these three verses. Two other verses with this in it (while they have more confusing factors and are not as useful) are Romans 1:18 - 32, and Genesis 19.