Listen to your one of your own prophets then:
“Those who cannot remember the past are condemned to repeat it."
George Santayana
(he was an atheist too).
You just made a totally baseless claim. As a Christian I feel obligated to warn if someone is representing a wrong picture of Christianity.
You use Bible as science books instead of source of spiritual information. You seek words of flesh.
I have never denied demonic possessions. I just wanted to point out that in the past they didn't distinguish between demonic and non-demonic issues (independent mental/physical issues). They just didn't have this knowledge. Here is the official position of the Catholic Church:
"1673.
When the Church asks publicly and authoritatively in the name of Jesus Christ that a person or object be protected against the power of the Evil One and withdrawn from his dominion, it is called exorcism. Jesus performed exorcisms and from him the Church has received the power and office of exorcizing. In a simple form, exorcism is performed at the celebration of Baptism. the solemn exorcism, called "a major exorcism," can be performed only by a priest and with the permission of the bishop. the priest must proceed with prudence, strictly observing the rules established by the Church. Exorcism is directed at the expulsion of demons or to the liberation from demonic possession through the spiritual authority which Jesus entrusted to his Church.
Illness, especially psychological illness, is a very different matter; treating this is the concern of medical science. Therefore, before an exorcism is performed, it is important to ascertain that one is dealing with the presence of the Evil One, and not an illness."
(Catechism, emphasis added)