In trying to get to grips both with Bryden Black's argument (which I unashamedly lean towards) and Tobias Haller's argument (which I unhesitatingly respect as reasonable and fair) I shall try to be fair!
Useful for below:
'So God created adam in his image,
in the image of God he created him,
male and female he created them.' Genesis 1:27
'There is no longer Jew or Greek, there is no longer slave or free, there is no longer male and female; for all of you are one in Christ Jesus.' Galatians 3:28
'For a man ought not to have his head veiled, since he is the image and reflection [glory] of God, but woman is the reflection [glory] of man.' 1 Corinthians 11:8
'For the husband is the head of the wife just as Christ is the head of the church, the body of which he is the Saviour ... For this reason a man will leave his father and mother and be joined to his wife, and the two will become one flesh. This is a great mystery, and I am applying it to Christ and the church. Each of you should love his wife as himself, and a wife should respect her husband.' Ephesians 5:23, 31-33
A few reflections (some of which I think I have already made inter alia among previous comments).
1. I think it an error to call up the interpretation of the ancients on Genesis 1:27 (Haller) to rebut a (so-argued) novel reading of Genesis 1:27 (Black) in the context of arguing for a novel interpretation of marriage (Haller). It is quite fair and reasonable that a review of the biblical material on marriage towards adopting same sex marriage is a free review of all material, including the possibility that a new reading of Genesis 1:27 counts against that adoption.
2. Although it took me a while to understand the force of Tobias' argument that the third line of the three line statement about creation imago dei in Genesis 1:27 is in 'opposition' rather than 'apposition' to the two previous lines, I understand him to be arguing that God created adam in God's image but did not create humanity divided into the sexes in God's image. That is, what we 'image' is neither the diversity of God through being diversely gendered nor the creativity of God through being humanity-enabled-to-be-procreative-by-being-male-and-female. A strong argument which claims properly that it is a plain and careful reading of the words of the three lines.
3. The apposition argument from Bryden is that God creates humanity-that-is-male-and-female in his image. (Funnily enough, yesterday reading a book about Jacques Ellul, I noted that Ellul understood Genesis 1:27 in the apposition way, God created one person in two forms (with obvious analogy back towards God-one-being-in-three-persons).) The strength of this argument is that it allows the word 'created' to be what it is, a connection between all three lines so that the third line is an extension of the second line rather than an opposition to it: in the image of God he created him = adam = male and female.
That male and female each bear the image of God is the least the third line means (and thus we read what we read in 1 Corinthians 11:8: the man images God, the woman images the man who images God) but might we also take account of Genesis 5:1-2,
'This is the list of descendants of Adam. When God created adam, he made him in the likeness of God. Male and female he created them, and he blessed them and named them adam when they were created.'
Humanity is expressed by the adam (man) but the writer of Genesis 5:1-2 understands humanity in its gender diversity, composed of zcr and tqbh, male and female, as created by God: not (as in Genesis 2, reflected in 1 Corinthians 11) primarily male with female derivative from male (or female as an improvement on male), but both together.
Genesis 5:3 is then important:
'When Adam had lived one hundred and thirty years, he became the father of a son in his likeness, according to his image, and named him Seth.'
The image of God 'became the father of a son in his likeness, according to his image.' Inherent in the understanding of being made in the image of God is the creative power to make others in that image. That happens because humanity is male and female. Without being male and female, humanity could not act in this God-like manner. Humanity male and female is a creation in God's image because together (and only together) male and female act like God in themselves procreating sons and daughters in their likeness.
If we are going to talk about plain reading of texts, are we not reading plainly as Trinitarian Christians when we see humanity as one person (adam) in two forms (zcr, tqbh)?
In sum: while seeing the strength of Tobias' argument against reading Genesis 1:27 as God made humanity male and female in his image, I am not overwhelmed by that strength. The apposition argument may not be so strong as to sweep the opposition argument before it, but it is a strong argument.
(As an aside, it is ironical that the NRSV, much valued for its inclusive approach to translation, makes Genesis 1:27 perfectly suited to support Bryden's argument! 'So God created humankind in his image, in the image of God he created them; male and female he created them.')
4. I accept that in heaven there will not be marriage and thus sub species aeternitas (from the perspective of eternity) marriage is a temporal phenomenon. Yet this observation needs care. Our physical bodies, for example, are also temporal (beyond the grave we will have new spiritual bodies). But dare we treat them as a kind of passing phenomenon? If we did, we could be quite cavalier about each other's bodies: I know this will kill you but it is only your temporal body ... of course not!
The precise paradox of temporality of the phenomena of this world is that we respect one another as God's creatures and do all in our power to prolong each other's lives, through health, through peace-making, etc while understanding that (in a sense) all this is in vain as all die and all institutions of this life fail (save for the church?). Gender and marriage may not survive death and judgment but that does not and should not lessen the importance we attach to them in this life.
5. One importance which attaches to marriage is that it is a great and repeated metaphor for the very relationship between God and God's people and between Christ and Christ's church. But how does this metaphor work? It works from an understanding of marriage in which the two parties to the marriage are differently gendered so marriage consists of a male husband and a female wife, a point reinforced in (say) Ephesians 5:23 where marriage is understood to involve headship, a specific relationship between husband and wife which itself mirrors and sheds light on the headship of Christ over the church. The great mystery of marriage, Ephesians 5:31, is then both the 'one flesh' coming together of the man-who-leaves-his-mother-and-father and the woman to whom he is 'joined' as she becomes his wife and he her husband. Paul does not quite say it, but the great mystery likely includes the way in which two are one flesh even as one is head of the other: this is a great mystery for how are the two joined in marriage equal partners in one flesh while being unequal (or 'unequal') in respect of headship.
Whatever we make of headship and of the understanding and application of Paul's teaching about it in today's world, the point is that marriage is understood here (and elsewhere in Scripture) to be gender differentiated. This is not merely as a matter of biology (the coming together of which differentiated bodies to form one united body through intercourse is basic to 'one flesh'), or psychology (the coming together of two people to form one couple united in heart, mind and will is also reasonably included in the meaning of 'one flesh'), but also of relationship to one another in the gendered roles of husband and wife. Husbands are to love their wives; wives are to respect their husbands. Men in marriage are asked to be responsible for their wives in a specific way, women in marriage are asked to be responsible to their husbands in a specific way.
This approach to marriage works well in terms of metaphor. Christ is not the church; the church is not Christ, yet Christ loves the church (like a husband loves his wife), the church submits to Christ (like a wife submits to her husband) while Christ and the church are united as 'one flesh', a head (Christ) and a body (the church) forming one entity. There is indeed a great mystery here.
Now polygamous marriage would not offer a metaphor here and nor would same sex marriage. The important question then, I suggest, working from the Haller-Black debate, is whether the approach to marriage taken in Scripture rules out the possibility of same sex marriage.
Obviously same sex marriage is not ruled out just because it cannot be invoked metaphorically in the service of Christ and the church. Further, we observe that polygamous marriage finds a place in the Bible. But polygamous marriage has a checkered career through the history of Israel (and no place at all in the movement of Jesus). The focus on marriage in Ephesians 5, anchored as it is into Genesis 2, rules out the possibility of Christianity endorsing and promoting polygamy: Christ is one and there is one church.
Having connected marriage to christology and ecclesiology in the manner of Ephesians 5, there is no going backwards for the church to re-think marriage as re-extendable to incorporate polygamy. The consequence of involving marriage as a metaphor for Christ and the church is that Christ and the church confines understanding of marriage to rule out polygamy. In case of doubt one may also refer to the teaching of Christ himself on marriage which in similar fashion (including anchoring on the rock of Genesis 2) only envisages marriage being between two people, not more.
What bearing then does Ephesians 5 have on same sex marriage? I suggest it makes it that bit harder to say that the Bible in the end is indifferent to the gender of parties to a marriage.
6. Nevertheless arguments will spring forth (and back) re the expandability of the definition of marriage. Sticking with Ephesians 5, for example, the case can be made (as Tobias does) that the connection between husband and wife in terms of roles re 'love' and 'respect', betokening as it appears an inequality, is lessened today if not done away with, so that consequently a distinctive aspect of gender difference in marriage is done away with. Cue the possibility of marriage indifferent to gender.
But this works in another way. Engaging with Ephesians 5 (and not only with Ephesians, but simplicity keeps me focused on this chapter) directs us to the particular significance of marriage between a man and a woman, a marriage which creates a husband and a wife, both with attendant responsibilities and potent metaphorical attribution. Is this form of marriage sui generis? If 'marriage' is a word to also be used of a relationship between two men or two women, do we need another word for what Ephesians 5 talks about?
7. Another way to put my concerns at this point is this: if we approach the definition of marriage by testing what is essential and what is inessential we find a case mounts for gender differentiation to be placed in the inessential rather than essential category. Ergo, same sex marriage is plausible as marriage. But if we approach proposals for what constitutes marriage (e.g. heterosexual marriage, same sex marriage, polygamous marriage) and ask whether heterosexual marriage, that is, the embodied union of two differentiated genders, is a distinctive class or category of marriage, then answer is affirmative. The question then is not whether all marriages fit an agreed definition of marriage, but whether we have the right names for distinctive relationships.
In part this question will be answered by the course the English language takes. In another part the question could be answered by theologians finding a specific word or phrase to describe the marriage between a man and a woman.
I may add to this but I will post for now ... 12.19 pm NZ time, Monday 23 September 2013