The Deceitfulness of Sin

Have we pondered long enough about the  "deceitfulness of sin" to understand its danger?  

If we think we stand firm, we should take heed lest we fall;  sin's deceitfulness will "harden the heart".  

Why are we told to exhort one another daily, and how does this exhortation work to prevent the deceitfulness of sin from hardening our hearts? 

Does it not seem likely that the deceitfulness of sin hardens the heart against receptivity towards the truth?  

Deceitfulness wars against truthfulness, so it follows that a heart being deceived by sin will become more and more resistant to the truth.  Isn't this what Paul warned would  happen when men "will no longer endure sound doctrine?"   As the heart is hardened by the deceitfulness of sin, men turn their ears away from the hearing of the truth.  They will reject teachers that they once esteemed, and gather new teachers around them who are not teaching  sound doctrine, just "myths".  The Greek word for "myths" simply means "sayings"; myths are just ideas men teach from their own creative minds that are not true sound doctrine.  These ideas and their popular proponents can be very appealing.   Many eloquent myths will sound wise, philosophical, uplifting, even inspired - but something is terribly wrong when the heart welcomes a myth and winces at the truth.

Men who are loving the truth are not as vulnerable to being led astray by fine sounding myths, but sin will quickly  begin to deceive us if we do not guard our hearts very carefully. A heart being hardened by the deceitfulness of sin will begin to wrestle with sound doctrine and eventually reject the truth. The myths will lead such men to believe a lie, because myths are more appealing to carnal desires.  

The Spirit of truth reproves sin and carnality as evil; whereas, popular myths redefine grace to allow greater liberty of conscience. This is the reason many will abandon the faith once they have begun to believe the lie; because, the deceitfulness of sin hardens the heart against the disciplinary love of the truth.

Sin will cause love for truth to wax cold, and soon sound doctrine will begin to irritate more than it edifies.  Once this occurs,  discipline and reproof begin to be despised and viewed as oppressive and judgmental,  after the deceitfulness of sin has influenced the heart with the lie of carnal liberties.  

These "myths" promise greater freedom of choice based upon a "deeper" understanding of God's tolerance and tenderness.  The myth creates a new image of God, more sympathetic, less severe, and this appeals to men's sinful desires.   The myth rejoices at the kindness of God but rejects His severity all together.  All who love the truth of God will respect His severity and love His discipline. Men who begin to resent His discipline will soon reject His truth - once the heart has been hardened by the deceitfulness of sin.