If perfection were not possible, Christ would not have given us Christianity.
Yet perfection is not what people think: it has to be earned. We have to restore the purity and innocence of Eden within ourselves, and to do that, we have to change. A lot. That is, the devil — who is inside of us, not outside — has to be conquered. That devil is in your mind.
Be ye therefore perfect, even as your Father which is in heaven is perfect. - Mat 5:48
The one who leads us to perfection is Christ, whose example we must follow: sacrificing ourselves for others, and eliminating all of our imperfections. The imperfect cannot return to Eden.
"Amen, amen, I [Christ[ say unto you: I will perfect you in all mysteries of the Light and all gnoses from the interiors of the interiors to the exteriors of the exteriors, from the Ineffable down to the darkness of darknesses, from the Light of lights down to the... of matter, from all the gods down to the demons, from all the lords down to the decans, from all the authorities down to the servitors, from the creation of men down to [that] of the wild-beasts, of the cattle and of the reptiles, in order that ye may be called perfect, perfected in all fullness. Amen, amen, I say unto you: In the region where I shall be in the kingdom of my Father, ye will also be with me. And when the perfect number is completed, so that the Mixture shall be dissolved, I will give commandment that they bring all tyrant gods, who have not given up the purification of their light, and will give commandment to the wise fire, over which the perfect pass, to eat into those tyrants, until they give up the last purification of their light.” - Pistis Sophia