What does “the mother of us all” mean (Galatians 4:26)?

Galatians 4:26 says, “But the Jerusalem above is free, which is the mother of us all” (NKJV). In the larger context of this verse, Paul contrasts two women, representing two covenants: Hagar represents the covenant of law, and Sarah represents the covenant of promise. Hagar was a slave, and her figurative children are in bondage to the law. She “corresponds to the present city of Jerusalem” (Galatians 4:25). Sarah, the freewoman, has (figurative) children who are born of the promise of God. She corresponds to “the Jerusalem that is above” (Galatians 4:26).

Genesis 16 relates that Abraham married Sarah, but they were initially unable to have children. Rather than trusting God with their future to produce an heir, Abraham and Sarah took matters into their own hands. Sarah gave her slave Hagar to Abraham as another wife. Abraham slept with Hagar, and she became pregnant and bore a son named Ishmael. Later, as God had promised, Sarah herself became pregnant and bore a son named Isaac (Genesis 21).

Hagar and Sarah, and their sons Ishmael and Isaac, are referenced in Galatians 4:21–31. Paul describes Ishmael as the son “born according to the flesh” to the slave woman (Galatians 4:23). Paul then likens Hagar to Mount Sinai and “present Jerusalem” (verse 25, ESV). At the time Paul wrote Galatians, Jerusalem was the epicenter of Jewish religious life based on strict observance of the Mosaic Law. Paul uses Hagar and Ishamel to represent the Old Covenant based on adherence to the law. That system, which appealed so strongly to the flesh, was centered in the physical, earthly Jerusalem of his day.

Paul then describes Isaac as the son the free woman who was “born as the result of a divine promise” (Galatians 4:23). Paul makes the symbolic connection between Isaac and New Testament believers in verse 28: “Now you, brothers and sisters, like Isaac, are children of promise.” That is, when we are born again into God’s family, we are born free from the dictates of the law. We are part of God’s family on the basis of God’s gracious promise in Jesus.

Paul then refers to Sarah as “Jerusalem above” (Galatians 4:26, NKJV). The phrase Jerusalem above is a creation of Paul’s and not found elsewhere in Scripture. He uses it as a reference to the New Covenant—God’s plan of salvation brought down from heaven to earth through the Incarnation of Jesus. In the heavenly Jerusalem, it is not one’s works that matter but God’s promise in Christ.

Paul continues the symbolism, saying that Sarah is “the mother of us all” (Galatians 4:26, NKJV). The “mother” here is another reference to the New Covenant that Christ established through His life, death, and resurrection. It is a covenant based on God’s promise of grace through faith, not on obedience to the Old Testament laws. The “all” in the verse, then, is a reference to anyone who has placed his faith in Christ for the forgiveness of sins. Just as Abraham’s inheritance went to Isaac and not to Hagar’s son, so those today who are born again will receive a heavenly, eternal inheritance that those in bondage to the law will never know.

Performing works of the law cannot save anyone (Galatians 2:16). Only grace through faith in Christ can save (Ephesians 2:8–9). “Everyone who calls on the name of the Lord will be saved” (Romans 10:13) and can be considered children of Abraham and Sarah, a couple whose faith saw the fulfillment of God’s promises.