Christianity has been around for a couple of thousand years so you might assume there's nothing new to say about it, but academics are always reinterpreting history. Charmian Smith talks to Prof John Barclay about some of the latest thinking about the life, death and resurrection of Jesus.
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Two thousand years ago, the new movement managed to challenge the Roman empire's value systems, radically changing the normal ways of thinking about hierarchy, he said.
He is also fascinated to find out why it was the fastest growing of several religious movements in the empire, spread through all classes and races and is now a worldwide religion that reaches all social levels.
Prof Barclay, Lightfoot Professor of Divinity at Durham University, UK, is on sabbatical at the University of Otago to work on a book about the apostle Paul, who was one of the founding Christian theologians in the earliest years of the movement.
"Paul has some radical notions about gift which arise out of the nature of the death and resurrection of Jesus, which make him break the mould of the ways in which people thought about and practised gift-giving in the ancient world," he said.
Gift-giving has become peripheral in modern Western society, and we consider the best gifts are unilateral, but for most other cultures past and present, a web of reciprocal gift-giving bound societies together.
Over the past century, anthropologists and philosophers have studied how gift exchange operates in various societies, including Pacific and Maori societies, he said.
"I'm trying to bring together that study and studies of Roman society and put Paul in that mix and ask what is Paul doing that is different; how does he think about the death and resurrection of Christ, and how does that challenge ancient notions of gift?"
In societies where people tied themselves to others by giving and receiving gifts they had to be careful to whom they gave gifts.
You gave to people according to their social status, who would enhance your reputation.
There was no point in giving to insignificant people who were too poor or too worthless to tie oneself to in a gift relationship.
The male, the free, the powerful and the rational were favoured over the female, slaves, the weak, poor or uneducated, he said.
"So you have a set of interlocking hierarchies which determine how gifts are given. If this is so among humans, it's all the more applicable to how God or the gods give."
Most religions had notions of sacrifice, which is giving to God or gods, and in doing so developing a gift relationship with them like that between a client and patron.
People understood God or the gods maintained the proper order of the universe by giving gifts to fitting recipients with the right social, moral or intellectual qualities, he said.
"Now one of the ways in which Paul's thinking is very intriguing is that he interprets the life and death and resurrection of Jesus as a divine gift, but what is radical about it is that this is a gift given without preconditions, given in a way that flouts normal criteria of what is reasonable and sensible.
"The sorts of values that are embedded in the way people give gifts in antiquity are deeply challenged by the way God's gift is given to the unfitting, the undeserving, without regard to ethnicity, birth or lineage, without regard to moral status or achievement, without regard to gender, without regard to social status."
One of Paul's most famous statements, which was probably part of an early baptism formula was "There is neither Jew nor Greek, slave nor free, male nor female, for you are all one in Christ Jesus".
Paul saw that disregard of normal ways of ordering society arose out of this unconditioned gift, sometimes called by the theological term, "grace".
But beyond giving it to all people, the nature of the gift itself was extraordinary, he said.
Crucifixion was the most undignified, shameful and horrible form of death at the time. The very thought of a cross sent shivers down the spine of Roman writers like Cicero.
"It's hard for us to get this because the cross has become such a familiar Christian symbol - we cover it with silver and we take it as a rather bland kind of phenomenon."
In the ancient world, crucifixion was reserved for the worst criminals.
It was designed to break down their bodies and psyches by immobilising them, exposing them naked and lifted high, visible to a large number of people, while they died a slow, painful death.
"Paul dwells on that because he sees in this the fact that God's gift in the crucifixion of Jesus is the contradiction of all ancient notions of power and of honour. If God has decided to act in this totally monstrous way, then we have to rethink everything we thought we knew about power and common sense and everything we take for granted in terms of our values in the world," he said.
The early Christians were unique in the Roman empire in developing and fostering a different sense of loyalty, commitment and values from the norm.
Usually such unconventional ways of thinking only come about when some catastrophe happens or when philosophers, like the Stoics, have the time and resources to devote to new ways of thought, he said.
However, the early Christians saw crucifixion and resurrection as the moment that rescued and reordered the world and put humanity back in relationship with God in this previously unthinkable way.
"Early Christians thought the world had become out of kilter and we were out of proper relationship with God, that we had become estranged. But rather than waiting for us to get our act together, God had Himself acted.
"God had given Himself in Christ to rectify the world and put us right in relation to God - the life and death and resurrection of Jesus are the means to bridge the gulf between God and humans and set the world aright."
The early Christians tried to put their new way of seeing the world into practice and some of the things they did were radically different, such as challenging ancient family values, holding all things in common, or helping both Christians and non-Christians in need.
Whereas in the ancient world girls were married off when they reached puberty, the early Christians thought single women could serve God as well as married women.
"It frees women from the normal destiny of being the submissive wife and child-bearer, and there are some interesting examples of early Christian women who didn't marry and had a certain level of power," he said.
From the earliest days, Christians had social policies and cared for those in need, whatever their religion, status, race or gender, something that remains in some aspects of Christianity to this day.
In New Zealand it can be seen in the charity work some churches undertake to help the most vulnerable people in our society.
"It's often said it's remarkable that Christianity has become a worldwide religion and has reached all kinds of social levels.
"In India they were surprised to see Christians coming and trying to heal lepers of all people, and one of the fastest religious changes in India is the growth of Christianity among the dalits or untouchables," he said.
Although over the millennia the Church has often betrayed its own ideals and heritage, sliding back into normal cultural hierarchies of power, wealth and status, parts of Christianity have also managed to maintain its early ability to challenge normal convictions, which it can call upon to recentre itself, he said.
