READ: Gal. 4:21–26: … but the Jerusalem above is free, which is the mother of us all …
Paul points to the contrast that is already present in the Old Testament among the children of Abraham: Ishmael, born of the slave woman Hagar, was not conceived in faith but according to the flesh. He also did not live by faith. He was conceived through human reasoning, since Sarah had not become pregnant and Abraham was still physically strong.
Later, Ishmael’s actions toward his little brother also reveal that he did not act in faith (Gen. 21:9). It was different with Isaac: he was conceived in faith by the free woman Sarah and born through the promise. Both Sarah and Abraham were, humanly speaking, beyond childbearing, but they held fast to God’s promise.
So, from birth, Ishmael is a child of slavery (Hagar), and Isaac a child of freedom (Sarah). There is a significant difference between the two brothers, even though both are descendants of Abraham and both are circumcised.
Paul—guided by the Holy Spirit—assigns a symbolic meaning to this. The two mothers and two sons represent the difference between living under the law without grace and living by the promise.
Hagar and her children symbolize the church that lives by religious law. They are busy trying to achieve something through their own efforts. Sarah and her children symbolize the church that is truly free through faith in Christ. They also do good works, but from a place of thankfulness and not to earn the promise.
In fact, these two stand opposed: the enslaved church versus the free church. The enslaved church represents the earthly Jerusalem, home of the Jews with their legalistic works. The free church represents the heavenly Jerusalem, where Christ reigns with His grace.
This church has given birth to us as believers in Christ—she is the mother of us all. She holds the seed of imperishable life (the Gospel), through which the Spirit forms and nurtures us.
Whoever refuses to be her child also refuses to have God as Father (Calvin).
Does the freedom of the church have boundaries?
Sing: Ps. 125:1,2