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The majority of Paul's letters in the New Testament to the church center-in on one thing: Jesus Christ is enough for salvation.  There is no work in the law that any can do in order to be saved.

The Mosaic Law was never actually able to bring about holiness - not because the law was bad, but because man was bad, thus incapable of fulfilling it.  However, after centuries of Jewish culture grounded in God's old covenant law, Judaism's moralistic works of holiness were difficult to let go of for many people.  Jesus was, as the Scriptures said, "The stone that made men stumble and the rock that made them fall."  Many could not understand the truth that Jesus had died "once and for all."  Many continued in their works of moral goodness, which is why Paul labored so meticulously with them in explaining to them that the Scriptures they read as a list of rules to become holy were actually full of prophetic anticipation of the Messiah - the One who would wipe away every tear from their eye that the people cried because they could not keep the law, and take on all their sins from all their law-breaking.  Many people could not understand these things, so they continued - by the providence of God - in their works, only to die un-redeemed at the end of their miserable struggle to do enough good.

On the contrary, Jesus Christ is the fulfillment of the law.  Where the law was powerless to forgive sins, Jesus is completely powerful to forgive sins, since through His death He died for sin, and through His resurrection He lived for our justification - that God would impute to us Christ's righteousness.  Christ fulfilled all negative aspects of the law ("don't do these things or else you will die") and all positive aspects of the law ("do these things and you will live").  Christ died under the wrath of God for our sins (negative), and lived under the grace of God since He did not break one of God's commands (positive).  He is, therefore, the fulfillment of all God's holy law!  To be heirs with Him is even more astounding!

This truth, of course, led many to hate Jesus and His Gospel, which Paul preached.  They rejected the truth of God because they did not think they were that bad.  They had been deceived by the great deceiver to believe they could actually be like God.  Therefore, they hated Jesus because they saw no need for Him - and they hated anyone who spoke of their need for Him.  "Who does this guy, Paul, think he is?  We don't need help from God.  I'm not that bad.  I wish he would quit talking about my 'need for Christ'.  I don't need anyone's help.  A good God wouldn't let anyone go to hell anyway."

Today, just as in Paul's day, many people have continued in the deception that they don't need Christ.  They believe in a heaven, but only in their sense of the word: "Heaven will be a place where I get to have whatever I want!"  These same people, however, certainly cast out the idea of hell: "A good God wouldn't let anyone go to hell."  They think they don't have any need for Christ; they are too preoccupied with their life to think about their death.

Similarly, many professing Christians have also been deceived.  Many think, "I asked Jesus into my heart to save me.  Now, I have to try harder to be a good person so that I won't lose that salvation.  I'm such a bad Christian, though, because I keep on sinning."  And they heap work upon work on themselves, trying to be moral and upright.  The teachings of morality have some benefit to be sure, but they are not how "to work out your salvation with fear and trembling" (Philippians 2:12) or "walk in the newness of life" (Romans 6:4).  Instead, we are to seek the grace of God for justification, for sanctification, knowing it is He who wills and works for our good pleasure (Philippians 2:13), and it is He who began this good work in us; therefore, He will be faithful to complete it (Philippians 1:6).  Every Christian goes through times of ups and downs, times in the valley and times in the green pasture.  We must live in this tension of already saved, but not yet glorified.  Stand firm in this grace in which we now stand (Romans 5:2).

Living morally right as a Christian is fruit of the Holy Spirit's work of sanctification in the believer's life.  Yet, along with the doctrine of regeneration, this continual work of sanctification and the perseverance of the saints is perhaps the most misunderstood doctrine in the entire Christian sphere.  It is not the works of morality that save a person or keep a person saved.  It is the grace of God which justifies the ungodly for whom Christ died, and it is the grace of God which sanctifies the believer and works in them the moral law of God through His Holy Spirit.  It is the Spirit of God who is at work in the believer, "to will and to work for His good pleasure" (Philippians 2:13).  No amount of personal law-abidance or Pharisaical piety will make you holy.  It is only Christ, through the regeneration (the re-birth) of the Holy Spirit (John 3).

(For further, in-depth reading on this topic, read The Law of Christ by Charles Leiter.)

"The popular phrase, 'God loves the sinner, but hates the sin' must be re-evaluated in light of Psalm 5:5.  God not only hates the sin, but His hatred is also manifested against those who practice it!  How can this truth be reconciled with other passages of Scripture that speak of God's love for sinners?  Though God's wrath is revealed against the sinner (John 3:36), He has demonstrated His love by sending His Son to die for the very people who deserve only judgement (Romans 5:8, 10)" (The One True God, Paul Washer).