History records that the early Christin church believed in Reincarnation and of the souls journey back to oneness with God. This all changed by Imperial decree some 500 plus years after the death of Christ.
325 A.D. The failing Roman Empire, now under Constantin's rule, could not withstand the division caused by years of hard-fought, "out of hand" arguing over doctrinal differences. He saw it not only as a threat to Christianity but as a threat to society as well. Therefore, at the Council of Nicea, Constantine demanded that the Christians settle their internal disagreements and become Christ-like agents who could bring new life into a troubled, beaten-down empire.
Once the Nicea Council meeting was underway Constantine demanded that the 300 bishops make a decision by majority vote defining who Jesus Christ is. Constantine commanded them to create a "creed" doctrine that all of Christianity would follow and obey, a doctrine that would be called the "Nicene Creed," upheld by the Church and enforced by the Emperor. The bishops voted to make the full deity of Christ the accepted position for the church. The Council of Nicea voted to make the Trinity the official doctrine of the church.
There were indeed references to reincarnation in the Old and New Testaments. In A.D. 325 the Roman emperor Constantine the Great, along with his mother, Helena, had deleted references to reincarnation contained in the New Testament. The Second Council of Constantinople meeting in A.D. 553, confirmed this action and declared the concept of reincarnation a heresy
Emperor Justinian in 545 A.D. was able to apply the full power of Rome and his authority to stop the belief in reincarnation. He forced the ruling cardinals to draft a papal decree stating that anyone who believes that souls come from God and return to God will be punished by death. The actual decree stated:
"If anyone asserts the fabulous preexistence of souls, and shall assert the monstrous restoration which follows from it: let him be anathema. (The Anathemas against Origen), attached to the decrees of the Fifth Ecumenical Council, A.D. 545, in Nicene and Post-Nicene Fathers, 2d ser., 14: 318)."
The Emperor was determined to eradicate the belief even though the Pope and the church believed in reincarnation. The fact that the doctrine of reincarnation had been a part of Christian theology for over 500 years did not sway the Emperor.
Origen's writings were considered heresy by important cardinals in the sixth century. Origen's teachings had been considered as profound spiritual wisdom for three centuries. Origen lived around 250 AD and wrote about the pre-existence of the soul and in reincarnation. He taught that the soul's very source was God and that the soul's was traveling back to oneness with God via Reincarnation.
Emperor Justinian wanted Origen's writings and teachings to be condemned and destroyed but Pope Vigilius refused to sign a papal decree condemning Origen's teachings on reincarnation. As a result of his disobedience, the Emperor had the Pope arrested and put into jail. In 543, Justinian convoked the Fifth General Council of the Church and told the Pope he would sign whatever into doctrine whatever the council decided. On the way there, under guard, the Pope escaped to avoid being forced to condemn Origen's writings. The Emperor commanded the council to continue despite the Pope's refusal to attend.