(CBS) From the time of Jesus, there have been Christians in what is now Iraq. The Christian community took root there after the Apostle Thomas headed east. But now, after nearly 2,000 years, Iraqi Christians are being hunted, murdered and forced to flee -- persecuted on a biblical scale in Iraq's religious civil war. You'd have to be mad to hold a Christian service in Iraq today, but if you must, then the vicar of Baghdad is your man. He's the Reverend Canon Andrew White, an Anglican chaplain who suffers from multiple sclerosis and from a fanatical determination to save the last Iraqi Christians from the purge. White invited 60 Minutes cameras and correspondent Scott Pelley to an underground Baghdad church service for what's left of his congregation. White's parishioners are risking their lives to celebrate their faith.