And that means that anyone who tries to live by his own effort, independent of God, is doomed to failure. Scripture backs this up: "Utterly cursed is every person who fails to carry out every detail written in the Book of the law."
The obvious impossibility of carrying out such a moral program should make it plain that no one can sustain a relationship with God that way. The person who lives in right relationship with God does it by embracing what God arranges for him. Doing things for God is the opposite of entering into what God does for you. Habakkuk had it right: "The person who believes God, is set right by God - and that's the real life."
Rule-keeping does not naturally evolve into living by faith, but only perpetuates itself in more and more rule-keeping, a fact observed in Scripture: "The one who does these things [rule-keeping]continues to live by them."
Christ redeemed us from that self-defeating, cursed life by absorbing it completely into himself. Do you remember the Scripture that says, "Cursed is everyone who hangs on a tree"? That is what happened when Jesus was nailed to the Cross: He became a curse, and at the same time dissolved the curse.
And now, because of that, the air is cleared and we can see that Abraham's blessing is present and available for non-Jews, too. We are all able to receive God's life, his Spirit, in and with us by believing - just the way Abraham received it.