And the serpent said unto the woman, You shall not surely die:
Genesis 3:4
Plato Echoing Lucifer....and this FALSE DOCTRINE entered into Christendom...
"According to Plato, all things were not directly framed and regulated by the Supreme Divinity. ... 
But the fatal defect in his philosophy was the position he took concerning the mind, and its relation to the body and to the whole universe. He held that the mind or soul holds the same relation to the body that God does to the world.
The pre-existence of souls was a cardinal point in his philosophy, ...Like the Mormons, he held that not only men, but plants and all inanimate objects also, have souls, which existed prior to themselves. Thus, Prof. W. S. Tyler, of Amherst College, says:--
"There is no doctrine on which Plato more frequently or more strenuously insists than this,--that soul is not only superior to body, but prior to it in order of time, and that not merely as it exists in the being of God, but in every order of existence. The soul of the world existed first, and then it was clothed with a material body. The souls which animate the sun, moon, and stars, existed before the bodies which they inhabit. The pre-existence of human souls is one of the arguments on which he relies to prove their immortality."
"There is no doctrine on which Plato more frequently or more strenuously insists than this,--that soul is not only superior to body, but prior to it in order of time, and that not merely as it exists in the being of God, but in every order of existence. The soul of the world existed first, and then it was clothed with a material body. The souls which animate the sun, moon, and stars, existed before the bodies which they inhabit. The pre-existence of human souls is one of the arguments on which he relies to prove their immortality."
And that was the only means by which he could prove the immortality of the soul...Christians who adopt from Plato the doctrine of the natural immortality of the soul, have conveniently lost sight of the absurd and atheistical doctrine on which it rests. Some of the most eminent of the "Church Fathers," however, and especially Origen, accepted without question all the vagaries of Plato concerning the pre-existence of souls.
This theory was the logical outcome of his theory of the pre-existence of souls. In their pre-existent state, as a part of God, they knew all things; in coming into bodies, that knowledge was concealed; it was as though they had been stunned; still the knowledge was there, and the mind could of itself determine truth or error. Thus the mind of man is, according to Plato, the criterion to determine right and wrong. "It is the lord of itself and of all the world besides."
FathersOfTheCatholicChurch, E.J.WAGGONER