Sexual behaviors such as homosexuality are a big topic so I decided to do a post on what the Bible teaches on this. I will try to keep it from getting too complex though it will probably include a lot of scripture. With a few exceptions, most of the scriptures I'll reference are from the book of Romans.
The Bible doesn't address sexuality the way it is usually addressed in this day and age. It doesn't address homosexuality, or heterosexuality, or bisexuality, or whatever. The Bible talks about behaviors, about actions. In the world view our identity is often defined by something we consider a fundamental aspect of ourselves, such as sexuality, belief system, culture, a way of thinking, nationality/patriotism, career, or a personal passion for something. God's Word describes us as having a simpler identify. We are the sheep of his pasture. We are his temple, his dwelling place. We belong to Jesus. It is his thoughts towards us that define us; not our own thoughts, ideas, or passions.
Romans 1:5-6 (NIV)
Through him and for his name's sake, we received grace and apostleship to call people from among all the Gentiles to the obedience that comes from faith.  And you also are among those who are called to belong to Jesus Christ.
We are called to come out of the world in our way of thinking and our lifestyle. We are called to the obedience that comes from faith. If we have faith in God's thoughts and words towards us we will strive to walk or live in that. We are called to belong to Jesus.
1 Corinthians 6:18-20 (NIV)
Flee from sexual immorality. All other sins a man commits are outside his body, but he who sins sexually sins against his own body.  Do you not know that your body is a temple of the Holy Spirit, who is in you, whom you have received from God? You are not your own;  you were bought at a price. Therefore honor God with your body.
Sexual sins are sins against our own body and defile our body as a temple of the Holy Spirit. This is something that is very easy to overlook or ignore. Again, we are called to belong to Jesus. We are not our own. Honoring God with our body is important and sexual sins dishonor our body and dishonor God.
Romans 1:18 (NIV)
The wrath of God is being revealed from heaven against all the godlessness and wickedness of men who suppress the truth by their wickedness,
Major point here. God's wrath is revealed against those who suppress the truth by their wickedness, or suppress the truth by their actions. This is the foundational truth in this post. It is important to acknowledge truth by our actions and not suppress truth by our actions. Self-honesty can sometimes be extremely difficult to live out.
Romans 1:26-27 (NIV)
Because of this, God gave them over to shameful lusts. Even their women exchanged natural relations for unnatural ones.  In the same way the men also abandoned natural relations with women and were inflamed with lust for one another. Men committed indecent acts with other men, and received in themselves the due penalty for their perversion.
Because of suppressing the truth through actions, God gave these people over to shameful lusts. These are actions; behaviors that defile the body and dishonor God and his temple.
Romans 1:29-31 (NIV)
They have become filled with every kind of wickedness, evil, greed and depravity. They are full of envy, murder, strife, deceit and malice. They are gossips,  slanderers, God-haters, insolent, arrogant and boastful; they invent ways of doing evil; they disobey their parents;  they are senseless, faithless, heartless, ruthless.
Most of us read Romans 29-31 and see all kinds of "wickedness" in a stereotypical fashion. What we seldom see is ourselves. Yet Paul is setting the stage here for much of the book of Romans. We may feel that we would never murder someone yet we may gossip. We may think we would never be arrogant but sometimes we are. We may think children should obey their parents yet we often disobey our Father in Heaven. And all of this is lumped together with the wickedness of sexual sins. Gossip and homosexual behaviors are lumped together with being arrogant, slandering people (big at political election time) and disobeying parents.
Paul didn't write his letters in chapters and verses. The first verse in chapter 2 includes the word "therefore." Basically Paul was saying, "having said all of this about wickedness, here is my point."
Romans 2:1-3 (NIV)
You, therefore, have no excuse, you who pass judgment on someone else, for at whatever point you judge the other, you are condemning yourself, because you who pass judgment do the same things.  Now we know that God's judgment against those who do such things is based on truth.  So when you, a mere man, pass judgment on them and yet do the same things, do you think you will escape God's judgment?
Paul is speaking to the church here. If we break one of God's laws then we have broken all of his law. There is none righteous, not one. Paul's foundation in chapter 1 of the severity of suppressing the truth and the severity of wrath against sexual sins and wickedness wasn't to mark a particular group of actions as horrible, but to impart the severity of the sin we are all guilty of. And this is a truth we have to acknowledge in our actions, deeds, and words.
Jesus acknowledged this in how he handled the woman caught in the act of adultery.
2 At dawn he appeared again in the temple courts, where all the people gathered around him, and he sat down to teach them. 3 The teachers of the law and the Pharisees brought in a woman caught in adultery. They made her stand before the group 4 and said to Jesus, “Teacher, this woman was caught in the act of adultery. 5 In the Law Moses commanded us to stone such women. Now what do you say?” 6 They were using this question as a trap, in order to have a basis for accusing him.
But Jesus bent down and started to write on the ground with his finger. 7 When they kept on questioning him, he straightened up and said to them, “Let any one of you who is without sin be the first to throw a stone at her.” 8 Again he stooped down and wrote on the ground.
9 At this, those who heard began to go away one at a time, the older ones first, until only Jesus was left, with the woman still standing there. 10 Jesus straightened up and asked her, “Woman, where are they? Has no one condemned you?”
11 “No one, sir,” she said.
“Then neither do I condemn you,” Jesus declared. “Go now and leave your life of sin.”
Whether sexual sins, addiction to porn, gossip, arrogance, whatever; Jesus doesn't condemn. He does say go and leave your life of sin.
He says that to all of us.