1 Timothy 4:1-2

But the (Holy) Spirit explicitly and unmistakably declares that in later times some will turn away from the faith, paying attention instead to deceitful and seductive spirits and doctrines of demons, (misled) by the hypocrisy of liars whose consciences are seared as with a branding iron (leaving them incapable of ethical functioning).

There is a point of no return that a person can reach.  One compromise will lead to another until sin leads us entirely away from God.  Sin is not something we should give place to, and avoiding it is to our benefit.  Our faith developed in the truth and love of God is a barrier to deception and protection for us to eternal life.