Editor's note: Daniel A. Helminiak, who was ordained a priest in Rome, is a theologian, psychotherapist and author of “What the Bible Really Says about homosexuality" and books on contemporary spirituality. He is a professor of psychology at the University of West Georgia.

By Daniel A. Helminiak, Special to CNN

President Barack Obama’s support of same-sex marriage, like blood in the water, has conservative sharks circling for a kill. In a nation that touts separation of religion and government, religious-based arguments command this battle. Lurking beneath anti-gay forays, you inevitably find religion and, above all, the Bible.

We now face religious jingoism, the imposition of personal beliefs on the whole pluralistic society. Worse still, these beliefs are irrational, just a fiction of blind conviction. Nowhere does the Bible actually oppose homosexuality.

In the past 60 years, we have learned more about sex, by far, than in preceding millennia. Is it likely that an ancient people, who thought the male was the basic biological model and the world flat, understood homosexuality as we do today? Could they have even addressed the questions about homosexuality that we grapple with today? Of course not.

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Hard evidence supports this commonsensical expectation. Taken on its own terms, read in the original languages, placed back into its historical context, the Bible is ho-hum on homosexuality, unless – as with heterosexuality – injustice and abuse are involved.

That, in fact, was the case among the Sodomites (Genesis 19), whose experience is frequently cited by modern anti-gay critics. The Sodomites wanted to rape the visitors whom Lot, the one just man in the city, welcomed in hospitality for the night.

The Bible itself is lucid on the sin of Sodom: pride, lack of concern for the poor and needy (Ezekiel 16:48-49); hatred of strangers and cruelty to guests (Wisdom 19:13); arrogance (Sirach/Ecclesiaticus 16:8); evildoing, injustice, oppression of the widow and orphan (Isaiah 1:17); adultery (in those days, the use of another man’s property), and lying (Jeremiah 23:12).

But nowhere are same-sex acts named as the sin of Sodom. That intended gang rape only expressed the greater sin, condemned in the Bible from cover to cover: hatred, injustice, cruelty, lack of concern for others. Hence, Jesus says “Love your neighbor as yourself” (Matthew 19:19; Mark 12:31); and “By this will they know you are my disciples” (John 13:35).

How inverted these values have become! In the name of Jesus, evangelicals and Catholic bishops make sex the Christian litmus test and are willing to sacrifice the social safety net in return.

The longest biblical passage on male-male sex is Romans 1:26-27: "Their women exchanged natural intercourse for unnatural, and in the same way also the men, giving up natural intercourse with women, were consumed with passion for one another."

The Greek term para physin has been translated unnatural; it should read atypical or unusual. In the technical sense, yes, the Stoic philosophers did use para physin to mean unnatural, but this term also had a widespread popular meaning. It is this latter meaning that informs Paul's writing. It carries no ethical condemnation.

Compare the passage on male-male sex to Romans 11:24. There, Paul applies the term para physin to God. God grafted the Gentiles into the Jewish people, a wild branch into a cultivated vine. Not your standard practice! An unusual thing to do — atypical, nothing more. The anti-gay "unnatural" hullabaloo rests on a mistranslation.

Besides, Paul used two other words to describe male-male sex: dishonorable (1:24, 26) and unseemly (1:27). But for Paul, neither carried ethical weight. In 2 Corinthians 6:8 and 11:21, Paul says that even he was held in dishonor — for preaching Christ. Clearly, these words merely indicate social disrepute, not truly unethical behavior.

In this passage Paul is referring to the ancient Jewish Law: Leviticus 18:22, the “abomination” of a man’s lying with another man. Paul sees male-male sex as an impurity, a taboo, uncleanness — in other words, “abomination.” Introducing this discussion in 1:24, he says so outright: "God gave them up … to impurity."

But Jesus taught lucidly that Jewish requirements for purity — varied cultural traditions — do not matter before God. What matters is purity of heart.

“It is not what goes into the mouth that defiles a person, but it is what comes out of the mouth that defiles,” reads Matthew 15. “What comes out of the mouth proceeds from the heart, and this is what defiles. For out of the heart come evil intentions, murder, adultery, fornication, theft, false witness, slander. These are what defile a person, but to eat with unwashed hands does not defile.”

Or again, Jesus taught, “Everyone who looks at a women with lust has already committed adultery with her in his heart” (Matthew 5:28). Jesus rejected the purity requirements of the Jewish Law.

In calling it unclean, Paul was not condemning male-male sex. He had terms to express condemnation. Before and after his section on sex, he used truly condemnatory terms: godless, evil, wicked or unjust, not to be done. But he never used ethical terms around that issue of sex.

As for marriage, again, the Bible is more liberal than we hear today. The Jewish patriarchs had many wives and concubines. David and Jonathan, Ruth and Naomi, and Daniel and the palace master were probably lovers.

The Bible’s Song of Songs is a paean to romantic love with no mention of children or a married couple. Jesus never mentioned same-sex behaviors, although he did heal the “servant” — pais, a Greek term for male lover — of the Roman Centurion.

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Paul discouraged marriage because he believed the world would soon end. Still, he encouraged people with sexual needs to marry, and he never linked sex and procreation.

Were God-given reason to prevail, rather than knee-jerk religion, we would not be having a heated debate over gay marriage. “Liberty and justice for all,” marvel at the diversity of creation, welcome for one another: these, alas, are true biblical values.

The opinions expressed in this commentary are solely those of Daniel A. Helminiak.