Scripture
My old self has been crucified with Christ. It is no longer I who lives, but Christ lives in me. So I live in this earthly body by trusting in the Son of God, who loved me and gave himself for me.

Observation
Paul is addressing the question of whether Gentile believers should be circumcised. In other words, is it necessary to be Jewish to be a Christian?

As a Jew by birth, Paul knows that righteousness comes from faith in Christ not by obeying the law. No one can be made righteous just by obeying the law.

It's not a sin to find salvation in Christ and abandon the law. Rather it is a sin to put our trust fully in Christ and then to add the law to this.

The old self which needed the law to show the way to righteousness is now put to death in Christ. Now it is Christ who lives through us, and the way to live for Christ is to trust in him.

It the law could make us right with God, there would be no need for Christ to die. So to live by the law after we come to know Christ is to say that grace is wasted and there was no need for Christ to die.

Application
There is a fine line between establishing helpful principles for growing in Christ and falling into the trap of legalism.

We know that prayer, Bible reading, church attendance and helping others are essential to growing in our faith. These are good things but when we make our sense of “success” at following Jesus on the number of verses we memorise or the time we spend in prayer, we are saying that we can add to our relationship with God or that we can judge our own righteousness.

It's even worse when we make our rules the standard by which we judge the worth of other believers.

We are not saved by reading the Bible every day, speaking in tongues, worshipping on Saturday or any other rule we might seek to institute.

The good news is that I am saved by the awesome grace of God through the death of Jesus on the cross. There is nothing I can add or take away from that.

Prayer
Thank you Lord for your powerful awesome grace. Thank you that my standing with you doesn't depend on my performance, but only on your unchanging love. Amen.