Some Christians who have personal problems with homosexuality are all too eager to quote Leviticus 18:22:
You shall not lie with a male as with a woman; such a thing is an abomination. (NAB)
They might shiver with self-righteous titillation as they roll that last word around on their tongue. What they seem to not realize is that it's not the only thing that Holy Scripture presents to us as an abomination. Consider the following:
There are six things the LORD hates, yes, seven are an abomination to him; Haughty eyes, a lying tongue, and hands that shed innocent blood; A heart that plots wicked schemes, feet that run swiftly to evil, The false witness who utters lies, and he who sows discord among brothers. (Proverbs 6:16-19, NAB)
So haughty eyes (pride) and lying are also an abomination, as well as troublemaking.. Consider also:
Do you not know that the unjust will not inherit the kingdom of God? Do not be deceived; neither fornicators nor idolaters nor adulterers nor boy prostitutes nor sodomites nor thieves nor the greedy nor drunkards nor slanderers nor robbers will inherit the kingdom of God. (1 Corinthians 6:9-10, NAB)
See how heterosexual adulterers and fornicators (i.e., those having sex outside of marriage) are grouped along with "sodomites" as well as thieves, the greedy, drunks, slanderers, and, in general, the unjust? Or:
Now the works of the flesh are obvious: immorality, impurity, licentiousness, idolatry, sorcery, hatreds, rivalry, jealousy, outbursts of fury, acts of selfishness, dissensions, factions, occasions of envy, drinking bouts, orgies, and the like. I warn you, as I warned you before, that those who do such things will not inherit the kingdom of God. (Galatians 5:19-21, NAB)
What? No mention of homosexuality in this list, but it does include simple impurity? hatreds? (By the way, what does abomination mean? Look it up.) Outrage? Acts of selfishness? Any kind of immorality?? That seems a bit harsh, no?
Well, yeah, it would be harsh were it not for the grace of God freely given to us through Jesus Christ, which is the real message of the Gospel. As St. Paul said elsewhere, "all have sinned and fallen short of the glory of God," but he immediately goes on to say, "they are justified freely by his grace through the redemption in Christ Jesus." (Romans 3:23-4) Likewise, the passage from 1 Cor above immediately continues, "That is what some of you used to be; but now you have had yourselves washed [in baptism], you were sanctified, you were justified in the name of the Lord Jesus Christ and in the Spirit of our God." And the passage from Galatians goes on to list the fruits of the Spirit: love, joy, peace, patience, kindness, generosity, faithfulness, gentleness, and self control--these are built up in us by the Holy Spirit as we cooperate with the grace of God!
The message of the Gospel--the Good News--is that we can have hope, despite how utterly screwed up we are. It's not a matter of tritely saying "hate the sin; love the sinner." No, if we hate anything, it is all sin, and not because we find it personally distasteful but because we recognize that it pulls us away from our One True End, that is, it is a disorder.
You see, we are rightly and naturally ordered toward God--our End, our Goal--and all sin is by definition that which draws us away, that is, orders us in a direction away from Him. When the Catholic Catechism speaks of homosexuality as intrinsically disordered, this is what it means. In much the same way, it speaks of masturbation as a grave disorder, I might add.
The Catechism goes on to say that "Every sign of unjust discrimination in [homosexuals'] regard must be avoided," which is what I'm driving at here: If you condemn homosexual acts, you should in the same breath condemn selfish acts in general as St. Paul does, which includes any sexual acts that are not ordered towards procreation within the context of marriage. There is no room for special/more intense condemnation of homosexual acts in a rightly considered view of human sin.
But more importantly, Christians need to shift their energies from condemnation, disgust, or even hate and instead invest their energies in exhortation, compassion, and, indeed, charity. Yes, we do need to defend marriage, but frankly, that defense needs to be more encompassing and holistic--towards eliminating cohabitation before marriage, supporting greater fidelity within marriage, supporting people in natural family planning, working to reduce divorce, and generally working to better promote a holistic, positive understanding of human sexuality whose goal is to make people happier and healthier in this life as well as properly ordered toward eternal life with God. (The two go hand in hand.)
A defense of marriage that focuses exclusively on preventing the civil recognition of homosexual unions as "marriage" is almost certainly doomed to fail in the long run, and in the short run, it distorts the Christian Gospel and offers a terribly negative, lopsided, unattractive, and unhealthy view of the essentially positive Christian understanding of sex (and life in general!).