RTFA: http://www.youtube.com/watch?v=v-FHKyI1EyY&eurl=

Well, that got me thinking about a good story. You see, for about four centuries after Jesus died, early Christians hid their religion from the Roman empire. If you spoke out, the Romans would feed you to the lions. Christians were forced to pray in secret, and they buried their dead in vast, underground catacombs. Well, then in 391, Theodosius the Great made Christianity the official Roman religion. Now there are 2 billion Christians on this planet.