For all the exceptions and variations to faithful heterosexual monogamy that theologians may have discovered, the form that Christian marriage takes (whether an estate, ordinance, or sacrament) harks back to Christ's own reference to the Genesis narrative of human sexual differentiation and union. The starting point for His recorded position on the sexual ethics of His day is the Creation, not Jewish divorce laws, nor the authoritative oral law codified by the great rabbis who preceded Him.
Jesus is forthright about establishing the ancient account as the primary context for the understanding of marriage as normatively forming a kinship relation that supersedes all others in permanence to protect, support and guide the next generation that it creates. He roots his answers to the queries of His contemporaries in the fact that our God-given sexual differentiation imparts a strength of attraction that must override even filial ties in order to forge a new bond of permanent kinship that extends the human family. In essence, He’s saying ‘you can’t reverse kinship!’
On that basis, He declares the divorce laws to be a provisional (pastoral) accommodation: a recognition of the inability of any law by itself to effect fundamental changes in matters of the heart. Especially, in those whose resolve (marred as we are by the propensities of our fallen human nature) He had come to restore: ‘For what the law was powerless to do in that it was weakened by the sinful nature, God did by sending his own Son in the likeness of sinful man to be a sin offering. And so he condemned sin in sinful man.’ (Rom. 8:3). Note, He didn’t exonerate sin, but released the penitent from its guilt by punishing it, as He relinquished the human body of Jesus, His sinless healing Prince of eternal life, to the unthinkable humiliation and torture of a brutal execution.
St. Paul had a similar dilemma, as he provided marriage guidance to the Corinthian church. He couldn’t stray from the only additional divine revelation he had received from the Lord: 'Let not the wife depart from the husband’. It re-affirmed the teaching that Christ had shared with His disciples during His earthly ministry. Yet, the message was now addressed, for the most part, to Gentile civil marriages, where the wife had converted to Christ. A thoroughly novel situation. Pastorally, he extends a *limited* concession: 'But if she does (depart), she must remain unmarried or else be reconciled to her husband. And a husband must not divorce his wife.' (1 Cor. 7:11).
For all of his pastoral accommodations, the concession that he offers the wife, or husband with an unco-operative spouse is chaste separation, but not divorce. As the initiator of the marriage, a man must maintain the marriage to his unconverted wife, as long as she is pleased to remain united to him. I can’t imagine Paul, uncompromising as this text shows, would have affirmed same-sex marriage.
So, let the worldly and godless go their way and pursue homosexual civil marriage, ignoring Christ at their own peril. Let the true church refuse to allow their own rites of Holy Matrimony to follow this headlong rush towards the destruction of marriage as rooted in God’s purposes, the symptoms of which we see all around in our broken society.