There is an attraction to being “nice”. It would feel nice, and seem nice, to drop the Christian objection to Same-Sex Marriage. Steve Chalke – once a spokesperson for evangelicalism in Great Britain – has implied that evangelicals who oppose gay marriage are denying that God is love. It’s not nice to be on the receiving end of that comment. Secularists are convinced that orthodox Christian teaching on sexuality is ignorant and repressive; and if we won’t see the world their way, they will feel obliged to use the courts to re-educate us. It isn’t nice to read and re-read your articles to make sure you haven’t written anything which could lead to an appearance before an employment tribunal.

David Robertson’s recent critique of a Christian conference on marriage has led to the accusation that he isn’t nice. I’ve only met the Rev. Robertson once, very briefly, but he seemed perfectly amiable to me. However, it isn’t polite or genteel to criticise the progressive, media-friendly, charming Mr Chalke (by all accounts a smashing man, who does a lot of good work for charity but doesn’t like to talk about it). Of course, Christians are commanded to live at peace with their neighbours, love their enemies, seek the good of the city, and to have good reputations. And we are commanded to be compassionate, kind, forgiving, patient, disciplined, wise and loving. But I fail to recall a duty to seem “nice”.

It’s rather difficult to give any content to the concept of “niceness”. An Englishman, Scotsman or an Irishman will all have different conceptions of “nice” behaviour – never mind a German, a Tamil or a Yoruba. Different social classes will have different ideas of what constitutes “nice” behaviour, never mind different cultures! It seems to involve not upsetting your neighbour too much; we must, above all, be likeable. Yet Christians follow a man who said that he had come to drive family members apart.

The Messiah was good; he was love; he was the way, the truth and the life: but you could rarely accuse him of being nice. His followers must preach beliefs that are millennia old to a constantly changing culture. Sometimes, we’re not going to be liked. Sometimes, if we’re faithful to Jesus, we won’t seem nice no matter what we say or how we say it. Often, it’s better to face the front, speak directly to your audience, saying what you mean as if you actually mean it. People ought to know where they disagree with us and why.

And when it comes to marriage, Jesus’s beliefs are just going to annoy moderns. We can make one of three choices when confronted with Jesus’ teaching about marriage– what CS Lewis might have called a “trilemma”. We can believe that the gospels do not accurately record Jesus’ thoughts about marriage and sexual sin; or we can accept that the gospels do give an accurate account of Jesus’ mind on this subject. If we decide that the gospels provide an accurate record, we can either obey Jesus’ commands or we can reject his teachings as immoral and oppressive, delusions born of a patriarchal culture and scientific ignorance.

Do the gospels reveal what Jesus thought about marriage? Christians believe that Jesus was both fully God and fully man. Therefore, to understand Jesus we must understand him as a first century Palestinian Jew. In fact, scholars of all faiths (and none!) are united by the belief that we cannot understand Jesus if we do not place him in his historical context. Jesus was a Jewish teacher, loyal to the Torah and faithful to the God of Israel. Now, there is wide agreement that Jesus radically challenged common assumptions about the Torah and the Temple. Moderate voices are rarely crucified.

The gospel writers do not shy away from describing Jesus’ disputes with the religious authorities; indeed, these conflicts are at the centre of many of their narratives. Yet the gospels also casually reveal that Jesus expected his followers to make sacrifices at the Temple (Matthew 5 v 23-24; Mark 1v 43-44) and to obey the Jewish scriptures (Matthew 5 v 17-20). Jesus was Jewish; he did not tear down the faith of Israel to build the kingdom of God. Jesus tore savagely at self-righteousness, legalism and hypocrisy. He taught that entry into his kingdom began with repentance to God and faith in his messiah; this kingdom was for the outcast and rebel. Yet to repent is to turn away from our old ways; Jesus warned that those who enter the kingdom must be prepared for sacrifice, struggle and opposition (Luke 9v23; Matt 7 v13).

With all this in mind, we can approach Jesus’ teaching about marriage and sexuality. Modern readers might be shocked that Jesus opposed the more tolerant attitudes of his Jewish contemporaries. Teachers like the great rabbi Hillel had interpreted the law liberally, so that a divorce could be obtained for practically any reason. Instead, Jesus taught that God opposed all divorce. There is a great deal of debate about the meaning of the exception clause in Matthew’s gospel (Matt 19v9) but it is clear that Jesus believed that marriage ought to be a permanent union between one man and one woman.

Jesus rejected polygamy and taught that those who divorced for trivial reasons committed adultery when they remarried. In fact, every sexual act which took place outside marriage was sexual sin (“porneia”). So, Jesus defined marriage as the union of one man and one woman; he stated that this was God’s intention for marriage from the beginning; he taught that sex outside marriage was sinful; and he warned that those who live in God’s kingdom must be willing to deny themselves.

Critical scholars accept that these teachings go back to the historical Jesus . They appear in the earliest sources – Mark and the material common to Luke and Matthew. The sayings about marriage in Matthew and Luke are short, pithy, shocking and easily memorable. They fit Jesus’ historical context: one cannot understand the importance of these stories without some knowledge of second Temple Judaism. The story of the dispute with the teachers of the law in Mark follows the pattern of debates in early Judaism.

To all this we must add that every Jewish source from this period (and before) condemns homosexual acts. In fact, there is a tendency to see homosexual acts, and sexual permissiveness in general, as a “gentile” vice. The gospels are keen to report Jesus’ most controversial statements; they are also forced to respond to common Jewish criticisms of Jesus’ teaching. So if Jesus had rejected the Jewish ban on homosexuality we would have heard about it!

If we do not believe that the gospels record Jesus’ teaching about marriage, it is difficult to know which parts of the Gospel we can be certain about. To reject these passages would not merely be to reject evangelical beliefs about the inspiration of scripture. We would be effectively rejecting the belief that history can tell us anything about Jesus’ teachings. In that case, Jesus has nothing to say to us today because we cannot hear his voice.

The facts are quite simple. In common with Jewish thought, and the Jewish scriptures, Jesus believed that sexual activity should only take place within marriage. At the risk of stating the obvious, first century Palestinian Jewish teachers did not condone homosexual acts and every single scrap of evidence indicates that Jesus was not an exception to that rule. Unlike most of his peers he rejected polygamy, teaching that marriage was for one man and one woman. He was even more controversial when he insisted that God intended the union of one man and one woman to be permanent.

Jesus stance is far from unreasonable. Have we completely lost sight of the connection between sex and procreation? After all, there is a rather strong correlation between having a child and having had sex; there is an even stronger correlation between being human and having a biological mother and father. Marriage should recognise the basic facts of life: that sex is not merely for pleasure, affection and romance; that sex aims at procreation. And is it so ridiculous to suggest that we need a social institution which insists that our children matter more than we do?

This leaves us with a dilemma. Either we accept Jesus’ sexual ethics, and follow his teachings about marriage, or we reject Jesus’ teaching about marriage as heterosexist nonsense. Clearly, the second option isn’t open to the Christian. The Christian who rejects Jesus’ definition of marriage has set himself over and above Jesus’ commands. But a Christian, by definition, ought to be under the authority of Christ: after all, “Christ” means “king” and Christians believe that they are members of a kingdom.

Christians who wish to revise the Church’s stance on homosexuality tend to say that the Bible “is not as clear as we would like” or “these issues are not black and white”. Postmoderns, and those who hide behind their coat-tails, preach that there is something violent and oppressive in every claim to know the true meaning of a scriptural text. However, like it or not, some evidence demands a verdict. It is true that those following Jesus face many complicated personal and pastoral issues which are not easy to resolve. It is also all too easy to pass judgement on those fighting difficult personal battles. But Jesus stance on the nature of marriage is crystal clear. It isn’t nice to say it, but one must either accept his authority or reject it; there is no other option. He did not intend to leave one open to us.