Why Then the Law?: How God's Law Serves Faith in the All-Sufficient Christ

Brian Mahon - 11/12/2023


Text: Galatians 3:15-22


Likely against accusations that his Gospel makes the law pointless, Paul continues to explain the Bible's testimony to the grace of God. Drawing on a human example from the world of legal documentation, once a covenant (and its contents) are ratified, nothing can be added to nullify it. How much more a covenant that God has made and conditioned upon Himself? The promises God made to Abraham in Genesis 12 were finally to Christ. 430 years later, the law, being added, is no addendum or amendment to the covenantal promises God made in Christ. Those promises depend on grace and are made to faith in Jesus Christ. Why then did God add the law? To clarify sin as transgression while waiting on the advent of Christ. Thus, the law is not contrary to the promises. It served it by condemning us as guilty sinners, so that we'd be directed to the all-sufficient Christ, and to faith in Him

Sermon Outline:

  1. God's promises have always been promised to faith in Christ. (3:15-18)
  2. God added the law to serve that faith. (3:19-22)
    • By its being principally different than the promise. (3:19-20)
      And yet perpetually directional to it. (3:21-22)


Discussion Questions

  1. Read Galatians 3:15-22. Compare with the texts given for our call to worship and intermediate reading above.
  2. Read Romans 4:13-25. It's essentially an extended commentary on our passage. In 3:15-18, how does Paul argue from the lesser to the greater to support his point? To whom were the promises of God made? How does Paul argue for the offspring as the Christ? What covenant is Paul talking about? Does the law add anything to the promised grace of God? If not, why not?
  3. How do the terms 'blessing,' 'promises,' 'covenant,' 'inheritance' relate? Trace the 'blessings' or 'promises' of God from 3:6-3:18. What do you find that Paul includes in the blessings of the Gospel?
  4. If the inheritance is by promise and not by law, why was the law added? What's the 'difference' between sin and transgression? How does the law serve that difference? See Romans 4:15. Who gave the law? How does the address the likely accusation that Paul's Gospel denigrated the law or even made it pointless? Why was it put in place?
  5. If the law is no positive addition to the promises of God to faith in Christ, is it then contrary to the promises? Why isn't their a law that can give life and justification? Is the law the problem? If not, what is? How does Paul elevate the law again in 3:22? What great word does he assign to it? What did God's law do? Or how did it serve the faith by which the sinner is saved? What does it do to lead us to Jesus Christ? What unites us to Him and all the promises 'in Him'? What then of the law?

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