Apostles no tolerance for mixture

Galatians 1:6-10, 2 John 8-11

On the one hand the Apostle Paul battled against the mixture of law and grace.  And on the other John contested grace and license.  The Jews in Paul's sphere were trying to mix grace with works of the law of Moses, while John combated the gnostics who were mixing grace with sin.  The Apostles teach that Grace is the complete victory over sin; and the Christian need not rely upon the works of law to keep him righteous and holy; he can stand upon God's grace to overcome all sin.  This is what the Apostles contended with from the beginning and it is what we modern people of faith battle today.
Mixture is achieved when sin is viewed as greater than salvation.  Let me explain.  The general knowledge of believers is that sin is bad and needs to cease in the life of the believer.  Yet, we see that Christians continue to sin.  So, the Church must take up the cause to combat sin in the lives of its constituents.  One philosophy is like the Jews in Paul's time; hit him with the law.  The understanding is that the law will keep people in line.  Grace is too soft on sin it has to be mixed with grace in order to keep the believer in check.  The second philosophy is that if grace covers all then it really doesn't matter how believers act as long as they are "born again" and going to heaven.  After all we are "sinners saved by grace," and need merely to ask for forgiveness.  Both philosophies give greater power to sin than to the work of redemption and the power of the Holy Spirit.  Both of these philosophies are error.
Grace and truth are the power over sin.  It is God's unmerited favor that gives us the authority and stance we take over sin.  Paul says that it is the grace of God in which we stand.  A stance is not just where we are but a place in which we make a solid defense and offense against an enemy.  I think of one famous stand in history (well it didn't really work out to good) Custer's last stand.  (I couldn't immediately think of another.)  Grace is our out and out stance against sin.  We can't lose standing in God's unmerited favor; His grace is greater than all our sin.  We are saved by Grace (the power and stance of God's unmerited favor) through faith.  Our victory is actualized when we trust in grace over sin and death.  Faith unlocks the super-abundant power of grace over sin in our lives. 
Mixture weakens our stance, because we are not completely relying upon the Lord.  When we rely upon the law we are demonstrating that the work of Christ was not finished but man needs to do more to be right with God.  This is really offensive to God because it diminshes the work of Christ making it weak in regard to sin.  And when grace is mixed with license it proves that we believe sin is more powerful than the gift of God; the Holy Spirit.  Mixture empowers sin.