Some people live under the mistaken notion that salvation does nothing to them or for them except get them out of hell.  They think that they are still sinners who are only different post-salvation in that they will be saved from the consequences of their sin.  Thus, those who think this way tend to live the rest of their lives on earth with the belief that they are merely sinners who have been saved by grace.  Nothing much within them or about them has changed as far as they know, but they can at least rest easy that their continued sinning will be covered by the blood of Christ.  Praise God that His blood covers our sin, but the work of Christ on the cross and His triumph over the grave not only gets us into heaven but transforms us in the here and now.  Though the fullness of our salvation will not be worked out until we are revealed as the sons of God at Christ’s coming, we are in a process of transformation even now.  Our salvation has indeed left some permanent changes besides just the fact that we are going to heaven. 

Philippians 2:12 commands us to “work out your salvation with fear and trembling.”  Of course, the next verse reminds us that it is Christ in us doing the work according to His will and good pleasure.  Yet our work, as usual, is based in faith.  It was our faith by God’s grace that saved us, and it is faith that will enable us to be sanctified as we work out our salvation.  To work out our salvation means that we will live practically in the here and now more and more in light of who we are in Christ.  Thus, if we remain ignorant of all that Christ accomplished on the cross and by overcoming the grave, we may keep the sanctification process from going ahead full-steam as it ought to be. 

The Christian is no longer a sinner but a saint.  Paul repeatedly wrote to the saints at such-and-such a city (e.g. Romans 1:7, 1 Corinthians 1:2).  Never did he address God’s people as sinners, though he did call out sin that was present among the saints.  We are saints because we have a new identity that is found in Christ.  God sees us through the righteousness of Christ.  Not only are we “wrapped in a robe of righteousness,” so to speak, but God through Christ is working righteousness into our spiritual “DNA.”  Before we came to Christ, we were born sinners with the fallen spiritual “DNA” of Adam, the first sinner.  When we trusted in Christ by faith and repented of our sin, we were born again of the seed of Christ (1 John 3:9) by the Word of God which was planted in our hearts (James 1:21).  In other words, we were regenerated and reborn with a new DNA that is not programmed “sinner” but rather hardwired “saint.”  We are being changed from the inside out.  Righteousness is not just a robe to be worn to cover sin, but it is to be worked in to our very identity, nature, and being.  Salvation leaves with it a change, giving us the ability to no longer be selfish to the core and to have the power and strength in Christ to resist sin and our flesh by faith (James 4:7).    

2 Corinthians 5:17 says, “Therefore if anyone is in Christ, he is a new creature; the old things passed away; behold, new things have come.”  What exactly does this mean that we are new creations in Christ?  Romans 6:6 provides some insight when it tells us that our “body of sin” was “done away with,” having been crucified with Christ so that “we would no longer be slaves to sin.”  The old person (also called the old self or old man), which is who we were before salvation, is now dead because he (or she) was crucified with Christ.  Our old person with our old ways, ambitions, and bent to sin is now gone, having been put to death along with Christ on the cross.  When Christ rose to new life, He also made it so that we could have new life.  This is what it means to be a new creation- we are literally reborn to become a new person.  As a new creation, we ought to be more and more prone to righteousness and honoring God than to sinning, falling, and faltering.  Our old selves were enslaved to the law of sin and death, having no ability to fulfill the law of God.  Yet, having been born again, we now have the capacity by faith to obey and resist the pulls of our flesh.  We are not finished works in that we will still battle our flesh and its sinful urges, but inside we are new.  Our hope is that this new self indwelt by the Spirit of God can overcome the flesh.  We will still face temptation, but by faith we can trust God to provide a way of escape (1 Corinthians 10:13).  If we were still evil people to the core, we wouldn’t even be interested in the escape, but we would rather love our sin.  This change in internal desires is evidence of a new heart, one that is no longer desperately wicked and deceitful (Jeremiah 17:9) but one that can be given the desires of God (Psalm 37:4).  We as new creations in Christ need to continue to work out our salvation as Christ shows us that His ways are more desirable than the ways of the world.
There is great hope in being new creations in Christ with cleansed hearts.  We can even begin to have minds that think with Biblical priorities like Christ (1 Corinthians 2:16).  The only thing left to be changed is our bodies, which will be changed when Christ returns and glorifies us (1 Corinthians 15:53).  At that point, our human frailty along with our aches and pains will finally be gone.  There finally will be no more flesh to battle.  But until that day, the fight for faith is on, and we can win it daily by remembering just who it is we are in Christ (1 Peter 4:1-2).