Homosexuality is an incredibly difficult subject for two opposing sides to discuss. It is one of the few biblical sins by which people deeply identify themselves. Whereas someone addicted to alcohol may admit they are "an alcoholic," the term is generally descriptive, not the primary identifier of the core of a person. The belief of many that their sexuality defines them makes a biblical declaration of the sinfulness of homosexuality an attack on the individual, instead of the act and attitude. The topic is also difficult to broach because of the enemy's effective campaign to convince otherwise Bible-believing people that homosexuality is a particularly heinous, unforgiveable sin and those who partake are hated by God above all else. This is a lie, but an insidious, widely-held lie. With these difficulties humbly recognized, the issue still must be addressed.
Is homosexuality a sin?
First a short word on "sin." Sin has been defined as a transgression of law, rebellion against God, and an attempt to meet a legitimate need via a non-legitimate method. Sin is any action that harms the relationship we have with God and/or another person. It is choosing to act in a way that pulls us away from God. He designed us to respond to Him in a way that is in agreement with His nature. Sin breaks that connection, refuses that gift, and rejects God. Everyone sins. Every Christian sins. A Christian's life is not meant to be one filled with sin, but every single one of us chooses every day to act in a way that rejects God. A life freed from the control of sin does not mean sin is nonexistent in that life.
Homosexuality is one in a long line of sins. It is filling a need (love, affection, physical closeness) in a way counter to the way God designed humans to relate to Him and each other. The Bible does not say why God ordained marriage and a sexual relationship to stay between one man and one woman, but it is clear that He did. Several times in the Old Testament, God lays down the law concerning homosexuality (Genesis 19:1-3; Leviticus 18:22; 20:13). Paul reiterates this mandate, renewing the standard for the Christians in Romans 1:26-17 and 1 Corinthians 6:9. A common argument is that while Paul talks about homosexuality, Jesus does not. Defenders of the homosexual lifestyle choose to accept Jesus' loving nature and reject Paul, accusing him of latent legalism. It's an invalid argument. Jesus spent the great majority of His ministry in Jewish lands, surrounded by Jews who were very familiar with and quite faithful to the Old Testament law. He generally dealt with sin on a case-by-case basis (as he did with the Pharisees' hypocrisy and the woman caught in adultery). Paul worked with Gentiles, specifically Romans, in a culture where homosexuality was common. Much of his audience had no familiarity with the Old Testament law or its purpose. He needed to go out of his way to address the cultural issues they grew up with—including idolatry, adultery, and alcohol abuse.
Many argue that homosexuality is a congenital physiological condition. Even if that were so, it would still be a sin according to the Bible. The original sin of Adam and Eve irreparably damaged human DNA. Some of that damage induces individuals to sin in specific ways. Some are born without innate empathy; they are still responsible to allow God to work with them to express His love and kindness to others. Some have a predilection for substance abuse; they're still responsible to avoid addictive substances. People with an overwhelming obsession with sex are still required to fulfill those passions through sex within marriage. It is difficult, it is against our fallen nature, but part of choosing God means that He will help us as we attempt to align ourselves and our behavior with His standard. It does not mean that any of us will be completely free of our specific weakness, but it does mean we will have an opportunity to submit to God in our lives and work intimately with Him as He works in us.
The great choice for those caught in a sinful lifestyle is deciding if they are going to define themselves by that sin, or if they are going to set aside their limited point of view and define themselves by their relationship with God. It is important to note that it is not a sin to be unintentionally exposed to a temptation or to be predisposed to being tempted in a certain area. Rather, it is a sin to dwell on the thought of the sin, indulge in the possibility, and/or act on it. Yes, according to the Bible, homosexuality is a sin. But, it is no more a sin than any other sin. It is just as forgivable. It is just as conquerable (through the power of Christ).
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Truth about Sin