This section begins with a magnificent word picture of our salvation. We were all held captive under the law, imprisoned until the coming faith would be revealed. Until.
You and I were prisoners, shut up in our sins, with knowledge only of earthly things, with no chance of escape. The Law was a successful prison warden, keeping us in line. Reminding us of our condemnation. The Law is good if used as intended by God–to show us our inability to live righteously, to point us to a need for a true object of our faith outside ourselves. But the Law cannot justify or pardon, it keeps us in our place, holds us captive.
So then, the Law was our guardian until Christ came. Ahhh, the glory of the Gospel! Christ came! In the fullness of time, the reality we have all longed for, the One who could indeed pardon and rescue us from prison, came. And He frees us from the prison of our choosing. We have, all of us, sinned by choice. We followed our hearts affections toward idols, desires contrary to God’s goodness and beauty, and mud puddles. Our hearts deceived us, our desires failed us. Unless Christ came to free us, we would still be shut up in our sins. When He came to free us, it was to work in our hearts-renewing and reorienting our affections, and to open for us a door (He is the door! See John 15) that we may go about finding pasture and rest.
He came, that we might be justified by faith. Faith in Christ. And now that faith has come, that is to say--the true Object of our faith has come, we no longer need the ceremonial laws that point us to the need for an atoning sacrifice. We no longer need the laws that point us to our need for God to work in us, cleansing us and drawing us into community.
In Christ Jesus, we are all sons of God through faith. No one is born a son of God. Not one single human being. Not a physical descendent of Abraham, not a good person who keeps many of the laws, not those considered blessed by society–no one. We are sons of God through our union with Christ. And none of us are not treated as the Ancient Near Eastern culture treated daughters, or as the Israelites in Jesus’ time treated woman. In Christ, any who are of faith are sons. And therefore heirs. We have put on Christ, and no longer need to try to identify one another according to the flesh. In Christ we find out true identity, and we find the community we long for as we “are all one in Christ Jesus.” He changes us individually, and draws us into His family, true fellowship can be found nowhere else.
We are heirs according to promise. We cannot break through to the inheritance in any other way. He is the Way, the Truth and the Life. And He grants us the many precious promises (cf 2 Peter 1). He gives, we receive.