Summary: This passage of Scripture from Galatians is about what family Christians belong to, and what Christians look like. We look like our father
One in Christ
23 Now before faith came, we were imprisoned and guarded under the law until faith would be revealed.
24 Therefore the law was our disciplinarian until Christ came, so that we might be justified by faith.
25 But now that faith has come, we are no longer subject to a disciplinarian,
26 for in Christ Jesus you are all children of God through faith.
27 As many of you as were baptized into Christ have clothed yourselves with Christ.
28 There is no longer Jew or Greek, there is no longer slave or free, there is no longer male and female; for all of you are one in Christ Jesus.
29 And if you belong to Christ, then you are Abraham’s offspring, heirs according to the promise.
An American couple adopted a son from Korea and named him Eric. Several years went by. Eric was now five years old. The family was having lunch in a restaurant, and Eric made conversation with a boy at the next table. The boy asked Eric, “Why don’t you look like your mom?” Eric replied, “Cause she’s a girl.”
This passage of Scripture from Galatians is about what family Christians belong to, and what Christians look like. We look like our father. Galatians 3:26 (quickview)  says, “In Christ Jesus you are all children of God through faith.”
In the Galatian church, a faction existed that said believers must keep the Mosaic law if they wished to be truly Christian. It was not enough to be “in Christ Jesus,” you had also to keep the Old Testament dietary laws and the various customs and traditions of Judaism. In other words, they said you must be a Jew before you can be a Christian.
Paul knew that this was never going to work. The Gentiles would never convert to Judaism to become Christians. He also knew it did not make any sense. If we are made acceptable to God by keeping laws and regulations, we do not need Christ at all.
So Paul argues fiercely against these Judaizers. He reaches back behind the Mosaic covenant to the prior covenant that God made with Abraham. A period of more than four centuries lapsed between the time Abraham was deemed "righteous" before God gave Moses the Law on Mount Sinai (see Galatians 3:6 (quickview) ). For more than four centuries, Paul argues, Abraham and his descendants were declared "righteous" without the law.
In Galatians 3:23 (quickview) , Paul describes the true nature and function of the law. The Law was "our pedagogue." In Paul’s day, a pedagogue was a slave whose job was to supervise young children. The pedagogue was not primarily a teacher but an enforcer. He made sure strict rules of discipline and correct behavior were practiced. In other words, Paul says that the law of Moses was a preparation for Christ, and the Israelites were like minor children being prepared through the law to receive an inheritance.
Take another example: Edward VI, son of Henry VIII and Jane Seymour, was born in 1537. When his father died, Edward was nine years old. He became, in theory, king of England, but actually a "Council of Regency" governed until he came of age. Unfortunately, Edward never came of age. He died at age sixteen, and so he never fully came into his inheritance. Paul says that Israel was like the boy king Edward. They were children under a guardian, not able to fully access their inheritance. Their Guardian was the law, which kept them out of trouble until the time came for them to receive the promise.