Christianity began as a small Jewish sect among the common people in the Galilean countryside. The religion’s first writers lacked the education and sophistication of contemporary thinkers in the much larger pagan Greco-Roman world. Around the year 170, the pagan philosopher Celsus wrote a devastating polemic against Christianity. For 70 years, Christians were silent in response, in part, as a strategy (hoping Celsus’ book would be forgotten), but also because they lacked a theologian with sufficient training to respond. That changed with the coming of Origen of Alexandria, arguably Christianity’s first native genius. Having composed Christianity’s first systematic theology in the 220s, Origen went on to write a point-by-point rebuttal of Celsus in 248. John Hamer of Toronto Centre Place will look at Origen’s background, life, thought, and influence, including his posthumous condemnation as a heretic.