What is religion? In this book Christos Yannaras argues that it is a human construct, the product of our instincts of self-preservation and self-perpetuation, which bolsters our sense of security as individuals, promising us personal eternal happiness. Against this, Yannaras sets the commitment of faith, defining it as an act of trust, self-offering and self-transcendence. For a Christian, faith is lived within the ecclesial event, that is to say, within a mode of relations of communion embodied in Christ.