J John writes, ‘As I thought about black holes in this run-up to Easter, I found myself contrasting the idea of the black hole with the cross. There are comparisons - the black hole looks inward while the cross points out, takes in while the cross gives out, brings destruction while the cross brings life. Those opposing images could be principles that govern our lives. Do we take in or do we give out? Is our priority our own well-being or that of others? Do we focus on the fulfilment of our own desires or the concerns of those about us? Each of us must choose what principle we live under; to decide whether the geometry of our lives is the shape of the cross or the monstrous and ever hungry circle of the black hole. These two opposing principles are important when it comes to Christian involvement in society. We can choose to look inwards or outwards. Jesus constantly encouraged his followers to be salt and light.’