As far as Christianity and Paganism is concerned, it could be all the bad blood/history between them. You know, throwing the Christians to the lions for sport, and the later "witch hunts" by the so-called Christian organization.
One problem is that the Roman Empire after forcing Christianity on its population, burned many records and made up many lies about the transition.
Rome tradition was the most tolerant of multiple religions. They could not care if some group invented another god to their already numerous pantheon. Persecution for simple failure to worship the Emperor seems like bollocks to me. Some may have been executed, but there is no proof of widespread persecution prior to 393 CE. Most executions were for political crimes, insurrection, and common crime such as theft. Jesus of Nazareth was crucified (penalty for treason or insurrection) with the sign "Jesus of Nazareth King of the Jews." He was not criticised for claiming to be a god, which he never did claim.
Starting in 393 CE, Christianity had been in power over the Empire. Pagans were persecuted, temples closed or converted into Churches, holy springs desecrated, oracles were executed, and the Great Library of Alexandria was sacked by fanatical monks on orders of Saint Cyril. Hypatia the great Pagan Scientist and Philosopher taught the Greek science that differed from Jewish mythology. She was brutally murdered in a gruesome manner by Catholic monks on the orders of Bishop (SAINT) Cyril of Alexandria, in 412 CE.
Under Emperor Theodosius II, a widespread persecution and killing of Pagans as well as members of older Christian Sects who did not convert to Athanasianism. The number of Pagans, Jesus followers, Donatists, Arians, and Old Christians was likely in the millions. However, the Trinitarian Christian Empire destroyed all of the records as well as most of the gospels that it banned from the Bible. Many Pagans of course, and Old Christians converted out of fear for their lives. Others resisted, fled to the safety of Persia, the German Kingdoms, or recently freed Britain.
Paganism then and today was nowhere near as violent, hate filled, and genocidal as Trinitarian Christianity from 393 CE to the late Renaissance, and to some extent in America, a de facto Christian Theocracy.
Modern Pagans whom I have met along the Mersey River of England seem quite kind, friendly, generous, and really care about the Natural World. I love all Nature Religions. Christianity is an Anti-Nature Cult.
Wicca is a benign, nature loving faith, which I admire. It is a positive religion. Judaism, Christianity, and Islam are NEGATIVE RELIGIONS.
Neo-Pagans, Wiccans, Old Celtic Pagans, Native American Nature religions all impress me with their positive attitudes. I am not a believer but I consider some religions to be hateful and evil (Catholicism and American Evangelism.) I abhor the pain and suffering caused by Catholicism and Protestantism.
Unfortunately, Trinitarianism successfully erased the convicting evidence of their genocides, religious wars, torture, execution of pagans, scientists, and heretics, and torture/execution of innocent women on the lie of witchcraft.
You should ask what is wrong with Christianity. What is clear about what we call Christianity has nothing to do with the moral teachings of Jesus of Nazareth. Christians have done things condemned by Jesus.
If Jesus, the real man, was brought back, he would be condemned and rejected as a political candidate by the Tea Party Republicans. Even the Democrats would not let him run because of his certain defeat in modern America.
Amergin
