Railroad Track or Ladder?

On Galatians 2:15-21:

"God gave the law originally as a railroad track to guide Israel's obedience. The engine that was supposed to pull a person along the track was God's grace, the power of the Spirit. And the coupling between our car and the engine was faith, so that in the Old Testament, like the New Testament, salvation was by grace, through faith, along the track of obedience (or sanctification).

But this way of salvation is so uncomplimentary to the human ego (since God is having to do everything for us) it has never been very popular. The Pharisees, and many other Jews with them (as well as many people today), did an amazing thing. They took the railroad track—rails, ties, nails, and all—lifted it up on end, leaned it against the door of heaven, and turned it into a ladder to climb. This is the essence of legalism: Making the law into a long list of steps which we use to demonstrate our moral fitness to attain heaven. While the track is on the ground, some of the ceremonials ties could be pulled out from under the rails without ruining the track. But as a ladder, every rung is crucial, or you may not be able to climb the next.

This ladder is what Paul tore down. He tore down the legalistic misuse of the law. And he says (v. 18), "If I build up again those things which I tore down, then I prove myself a transgressor." You transgress the law of God when you try to erect the law as a ladder to heaven on which you will demonstrate your moral fitness for salvation. So the connection between verses 17 and 18 is this: When Christ leads us to trust him for justification instead of trusting our own legal (climbing) efforts, he is not an agent of sin, for what really makes a person a true transgressor of the law is not the neglect of its ceremonial statutes, but the horrible prostitution of the law of God which turns it from a railroad track of grace into a ladder of works. The transgression against God is to presume that you can climb your way up a ladder of morality into his favor."

John Piper
from I Do Not Nullify the Grace of God
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