Relevant Words of God:
As I have said, Satan has sent those who do service for Me to interrupt My management; these service-doers are tares, yet wheat does not refer to the firstborn sons, but rather to all the sons and the people who are not the firstborn sons. Wheat will always be wheat, tares will always be tares; this means that those of Satan’s nature can never change. So, in short, they remain as Satan. Wheat means the sons and the people, because before the creation of the world I added to these people My quality. Because I have said before man’s nature does not change, wheat will always be wheat.
from Utterances and Testimonies of Christ in the Beginning