Those opposed to gay marriage have argued that gay marriage will undermine the institution of the family. This point of view is often grounded in claims regarding the dysfunctional impacts of same-sex parenting, or on claims that such family structures are not ‘traditional’ in either a historical sense or theological sense. None of these claims carry weight.

One argument is that children of gay parents will face confusion and ridicule. But this is true only to the extent that society looks down upon same-sex parents and their children, and so this is not a problem with gay marriage as much as with a homophobic society. Its logic therefore is only in practical terms, but is not consistent with progressive reform aimed at a more rational, fair society.

Another argument is that gay parenting is not as effective as straight parenting. Given the amount of poor parenting that abounds, I find this difficult to believe. The question of whether being raised by same sex parents leads to worse outcomes for children is an empirical matter, and therefore requires empirical support. A recent paper by Loren Marks (2012) from Louisiana State University notes that no study has yet involved a sufficient sample size to report scientifically valid findings on this matter. Until substantive research is carried out, the assertion that same sex parenting impacts negatively on children is not a valid assertion.

What I suspect underlies the view that gay marriage is inappropriate is an assumption that only families with a mother and father are a ‘natural’ means of rearing children. What is often not realised is that the nuclear family structure is a recent invention. Many traditional societies raised children using an extended family model. Among Australian Aborigines, for example, children were more or less raised collectively by the tribe, with a child having several people they would refer to as mother, father, uncle, aunty, and so on.

Polygamous marriages have also been the norm in past societies. This was true among the Hebrews, for example, with polygamous families rife in the Old Testament. It is somewhat odd that Christian ministers should be the most ardent advocates of the nuclear family model of ‘mum and dad’ when, in many other instances, they draw on the Old Testament as an authoritative source for proper conduct.

The 5th century theologian St Augustine was aware of the contradiction, and attempted to explain away polygamy amongst the patriarchs as a deviation from God’s original plan, as evidenced by Adam and Eve. He wrote:

That the good purpose of marriage, however, is better promoted by one husband with one wife, than by a husband with several wives, is shown plainly enough by the very first union of a married pair, which was made by the Divine Being Himself (Of Marriage and Concupiscence, Bk.1, Ch.9).

This is quite a stretch by St Augustine, because it fails to acknowledge that unless God created a second woman from the ribs of Adam, there was no possibility for Adam to take a second wife. But by the 7th generation, Lamech we are told had “married two women, one named Adah, the other Zillah” (Gen 4:19).

Nowhere in the Old Testament does God condemn the taking of multiple wives. As usual, religious authorities are engaging in creative interpretation to try to reconcile textual traditions with modern Christian theology.

Polygamy is not addressed in the New Testament either, although 1 Timothy 3:2 recommends that bishops should only have one wife because they must be “above reproach”, implying that polygamy was associated with sexual delights (see 1 Corinthians 7:1-9). Despite the absence of scriptural support, the Catholic Church took it upon itself to declare polygamy as “not in accord with the moral law” and forbid its practice (paragraph 2387, Catechism of the Catholic Church).  Protestant churches subscribe to the same view, although many Mormons (unofficially) defend the practice based on the authority of scripture.

Hence, the view that families traditionally involve a single male and female parent is not borne out by historical and anthropological evidence, nor is it prescribed in Christian-Judaic scriptures. This is not to suggest that same sex parent families have been the norm at any time in the same way that polygamy has. On the hand, it was not unusual in the past, nor is it unusual now, for children to be raised in an all female household, or even an all male household, when the mother or father dies or leaves.

In conclusion, those appealing to the preference of mother-father parenting based on evidence, nature or tradition are on shaky ground. In the 21st century, where all manner of family structures prevail due to de-facto relationships, single parenting, blended families, adopted families, and so on, same-sex families should not be considered abnormal in any sense.

It should be kept in mind, too, that many same-sex families are formed in the aftermath of broken-down heterosexual relationships where the biological parent would otherwise be raising the child on their own. In such cases, critics are essentially making the case that the child would be better off with one parent instead of two same-sex parents.

None of this of course is directly related to gay marriage, because family structures in the modern age are not dependent on the marital status of the parents. In other words, same-sex parenting has, and will continue to, take place irrespective of whether gay marriages are legally recognised. The issue is indirectly related by virtue of the argument that the legal recognition of what types of marriage are appropriate or inappropriate are felt by many people to impact the norms concerning what sorts of parenting arrangements and family structures are appropriate or inappropriate.

The point I would make is that these structures will form anyway, so why continue to maintain an environment where these sorts of family arrangements are stigmatised and the children growing up in these families are made to feel abnormal? Surely this couldn’t be in the interests of anyone, and would only serve to extend prejudice from homosexuals to include their children as well.