In Paul’s Acts-period epistles, he revealed a mystery which had been given to him by God. This mystery was hidden in the Old Testament scriptures.

Rom 16:25-26
25 Now to Him who is able to establish you according to my gospel and the preaching of Jesus Christ, according to the revelation of the mystery kept secret since the world began
26 but now has been made manifest, and by the prophetic Scriptures has been made known to all nations . . . (NKJ)

This mystery related to the promise of the New Covenant which was pictured in the life of Sarah.

Gal 4:21-26
21 Tell me, you who desire to be under the law, do you not hear the law?
22 For it is written that Abraham had two sons: the one by a bondwoman, the other by a freewoman.
23 But he who was of the bondwoman was born according to the flesh, and he of the freewoman through promise,
24 which things are symbolic. For these are the two covenants: the one from Mount Sinai which gives birth to bondage, which is Hagar--
25 for this Hagar is Mount Sinai in Arabia, and corresponds to Jerusalem which now is, and is in bondage with her children--
26 but the Jerusalem above is free, which is the mother of us all. (NKJ)

Hagar, being a bondwoman, pictured the Mosaic Law (The Old Covenant) which kept the people in bondage to sin. Sarah, being free, pictured the New Covenant. At the last supper, the Lord Jesus took the cup of wine and said:

Luke 22:20
20 . . . "This cup is the new covenant in My blood, which is shed for you. (NKJ)

The shed blood of Christ provided God’s required atonement for sin and made possible the indwelling of the Holy Spirit which ushered in the initial phase of Israel’s New Covenant. The New Covenant was to be a covenant in which the laws of God were written in the hearts of the people by the power of the Holy Spirit. In Galatians 4, Paul said that the Old Covenant was given in relationship to the earthly city of Jerusalem which was under the bondage of Roman rule. He then concluded that the New Covenant was a covenant of freedom which will have its ultimate fulfillment when the heavenly city of Jerusalem comes down from heaven to the earth.

Paul reminded his readers that God had told Abraham to cast out the bondwoman and her son because her son could not be heir to the promise with the son of the freewoman. Paul’s point was that salvation can not come by a mixture of law and grace. It has to be one or the other. To be saved by the law one has to keep every aspect of the Law every minute of every day. To be saved by grace people have to believe that Christ died for their sins. Because the logic of this argument can not be disputed, I would pose Paul’s question of verse 21 to those today who wish to be saved by good works:

Gal 4:21
21 Tell me, you who desire to be under the law, do you not hear the law? (NKJ)

Write me at: jimjoan77@juno.com

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