From The Challenge of Jesus:

How are we to unlearn our meanings for such a phrase and to hear it through first-century ears? It helps if we can find another author using it at around the same place and time as Jesus. Consider, for example, the Jewish aristocrat and historian Josephus, who was born a few years after Jesus’ crucifixion and who was sent, in AD 66, as a young army commander, to sort out some rebel movements in Galilee. His task, as he describes it in his autobiography, was to persuade the hot-headed Galileans to stop their mad rush into revolt against Rome, and to trust him and the other Jerusalem aristocrats to work out a better modus vivendi. So, when he confronted the rebel leader, he says that he told him to give up his own agenda, and to trust him, Josephus, instead. And the words he uses are remarkably familiar to readers of the Gospels: he told the brigand leader to `repent and believe in me’, metanoesein kai pistos emoi genesesthai.

This does not, of course, mean that Josephus was challenging the brigand leader (who, confusingly, was called `Jesus’) to give up sinning and have a religious conversion experience. It has a far more specific and indeed political meaning. I suggest that when we examine Jesus of Nazareth, forty years earlier, going around Galilee telling people to repent and believe in him or in the gospel, we dare not screen out these meanings. Even if we end up suggesting that Jesus meant more than Josephus did – that there were indeed religious and theological dimensions to his invitation – we cannot suppose that he meant less. He was telling his hearers to give up their agendas, and to trust him for his way of being Israel, his way of bringing the Kingdom, his kingdom-agenda. In particular, he was urging them, as Josephus did, to abandon their crazy dreams of nationalist revolution. But, whereas Josephus was opposed to armed revolution because he was an aristocrat with a nest to feather, Jesus was opposed to it because he saw it as, paradoxically, a way of being deeply disloyal to Israel’s god, and to his purpose for Israel to be the light of the world. And, whereas Josephus was offering as a counter­agenda a way which they must have seen as compromise, a shaky political solution cobbled together with sticky tape, Jesus was offering as a counter-agenda an utterly risky way of being Israel, the way of turning the other cheek and going the second mile, the way of losing your life to gain it. This was the kingdom invitation he was issuing.