Heresy refers to beliefs that are distorted rather than representing a genuine form of Christian doctrine. Many heresies arose in the first five centuries of the church and the church's response to them is contained in its historic creeds. Other heresies are more recent. In this series we will look at two ancient heresies in Marcionism and Gnosticism and two more recent ones: the so-called Prosperity Gospel and the idea that Christianity = being nice. The aim is that by getting our thinking straight on the important issues involved, we will be able to live more faithful and healthy lives.