Galatians 6

But God forbid that I should boast except in the cross of our Lord Jesus Christ, by whom the world has been crucified to me, and I to the world.  For in Christ Jesus neither circumcision nor uncircumcision avails anything, but a new creation. And as many as walk according to this rule, peace and mercy be upon them, and upon the Israel of God.vv.14-16

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This short letter has come to a close and Paul sums up the aim of his letter.  And what was his aim? Basically that the the law is nothing and Christ is EVERYTHING!  
Just as Jeremiah said to boast in knowing God so Paul says that he will only boast in the cross of Jesus Christ, that great work He did by dying for the sins of the world that not one person could ever do or fulfill but God alone.  That's what matters is realizing the need for a savior and that Christ is the Savior that you need.  Nothing else matters for salvation for the Jew or the Greek or the Gentile.  What counts is a new creation and that is what you become when you believe on the Lord Jesus Christ as your savior.  Isn't that amazing?!?!  I mean think about it, it's human natural tendency to work to deserve something, but salvation is not earned by works, but all based on what Jesus did on the cross for us.  He must really care about us and value us to do such a great work like that.
How has understanding this aim of this letter brought peace and mercy on you?