A Very Great Misunderstanding

There is a misunderstanding in current Christian theology that is widely accepted by the believers. The misunderstanding is that people can walk in sin and self-will, not seeking to abide in the Person and way of Christ, and still remain under the pardon of Calvary by virtue of their acknowledgment of the theological facts concerning Christ: "we believe Jesus was born of a virgin; we believe He made an atonement for the sins of the world; we believe He rose from the dead on the third day."
No doubt the demons are well aware of these facts; yet, the demons do not have God’s forgiveness or one particle of eternal life. The fallen lords of the heavens shall one day bow the knee to the Lord Jesus but this will not save them in their wickedness.
The Scriptures are eternal: if we live according to the lusts of our flesh, and according to the dictates of our self-love, self-will, and self-centeredness, not forsaking our life and following the Lord Jesus, we will die spiritually. We will slay our resurrection to eternal life.
If any man, Christian or not, practices sin and rebellion against God’s will, he shall come under the judgment of God. If any believer in Christ puts to death, through the Holy Spirit, the lusts of his flesh, he shall enter eternal life.