Since theologians reflect upon what the church does and should practise in the light of the scriptures, it is nonsense for a theologian not to believe in what the church affirms (ie the Virgin birth, the resurrection of Jesus etc). Anyone who has accumulated knowledge in any intellectual sphere, be it knowledge about Christian theology or computer graphics, can teach what they have learnt. But to teach about the Christian faith and to be a theologian (to practise a discipline which is both intellectual and spiritual, addressed as is it to the church) are two very different things. No Christian non-believer can be a Christian theologian.
Graham Ward Professor of contextual theology and ethics, University of Manchester