In his book "The Future of Marriage," David Blankenhorn devotes an entire chapter (pp. 91 to 125) to the definition of marriage. He traces the history of marriage, the biology of marriage, different forms of marriage in different cultures, and focuses on fatherhood as the core meaning, or definition. Even so, I don't have the sense that he's entirely satisfied with his definition. It's terribly ironic, because there is a simple definition that has been written down for millennia, which really sums it up. That definition is found at the very beginning of the Bible, Genesis 2:24: "Therefore shall a man leave his father and his mother, and shall cleave unto his wife: and they shall be one flesh."
I always read this as meaning that they become one in sexual intercourse. But that's not what it means. You can have sex and not be married. It happens all the time. For that matter, you can be married in the physical, social, legal sense of the word, and not be married in the spiritual relationship that it is.
The key point, the crucial word, in this simple definition is "one." "They shall be one."
Marriage is a spiritual relationship, not a physical one – though it does have a physical component, which is embodied in the sexual relationship, but which is probably not necessary to consummate in order for the marriage to occur. In fact, marriage is probably the spiritual meaning or embodiment of sex, but that spiritual relationship is not contingent on ceremonies or legal documents or property exchange, or even a vow. It is an aspect of family, but family is more inclusive. Children are an aspect of it, but they are not necessary to it. Some "marriage defenders" put "responsible procreation" only within the boundaries of marriage, and in the spiritual aspect of it, I think they are right.
The problem is that Blankenhorn and other "marriage defenders" have limited the definition of marriage to the physical, social, and legal sense of the word. They have mistaken the finger pointing at the moon for the moon itself.
Notice the simple phrases that make up that one sentence definition. "A man [shall] leave his father and mother." A child, growing up, separates from his nuclear family, from the unity to which his mother and father belong. "…and shall cleave unto his wife." I emphasize "and" because it's not enough to separate from mom and dad. The adult child must also form a new relationship, which has a sexual connection or aspect – what Blankenhorn calls "pair bonding." "… and they shall be one flesh." Again the emphasis on "and," simply because there is no way to separate the two aspects. The "one flesh" is spiritual unity. By pair bonding in this way, those two people literally become one unit. That unit is marriage. It's like an molecule of water – atoms of hydrogen and oxygen bond to create a new element. And, like water, that element can be re-divided into its individual parts; but when that re-division happens, the element no longer exists. (That is divorce. And that spiritual divorce can happen with or without dissolving the physical-social-legal aspect of marriage.)
That spiritual unity, whole unto itself, is basic to humanity. It is part of our spiritual biology. Growing within it is the spiritual and emotional birthright of children, and that birthright should never be intentionally taken away.
In this, the "marriage defenders" are absolutely correct.
But what "marriage defenders" don't understand, is that the physical form of marriage is only the physical manifestation of a spiritual entity. The social institution of marriage, in whatever form it is manifested in the different cultures of the world – patriarchal, matrilineal, whatever – is how society honors, acknowledges, and recognizes this spiritual entity and unity. The form doesn't matter. And while the social institution of marriage is important in honoring and sanctifying the spiritual entity of marriage, in supporting the child and the child-rearing unit, it is not vital to it. Marriage will continue whether it is recognized by society or not, because it is at heart the joining of two individuals into one unit – and it is inherent to our species.
What they further don't understand is that gender is not a defining aspect of it. That sexual-spiritual unity exists among gay and lesbian relationships, and in my experience as a witness, is very common to those same-sex relationships. In other words, like it or not, gays and lesbians do marry, in the basic, spiritual-physical aspect that is the genuine entity of marriage – literally, the marriage of the Bible. The Bible puts it in terms of man and woman for good reason; by far the most common marriage relationship is between a man and a woman, and that is the form of the marriage relationship that produces children entirely within itself, and until the recent advent of IVF gestation and surrogate motherhood, the only way children were brought into being inside a married, family-childrearing unit.
So the first question we must ask in the marriage debate is whether we are going to define marriage as a purely physical relationship, or as the spiritual relationship it is. The health of the social institution of marriage is directly proportional to society's value and recognition of the spiritual entity of marriage.
The second question in the marriage debate is whether we as a society are going to find a way to honor those relationships between same-sex partners with a social institution, or whether we will continue to throw gay and lesbian families – gay and lesbian marriages, and their children – under the bus.
Then lets talk about how, within that framework, we are going to ensure that every child possible is raised with the birthrights of both family-childrearing unit and biological heritage intact.