Galatians 3:26–4:7 (NKJV)
26 For you are all sons of God through faith in Christ Jesus. 27 For as many of you as were baptized into Christ have put on Christ. 28 There is neither Jew nor Greek, there is neither slave nor free, there is neither male nor female; for you are all one in Christ Jesus. 29 And if you are Christ’s, then you are Abraham’s seed, and heirs according to the promise.
Galatians 3:26-29

Paul moves into a discussion of the access to faith provided to all people through Christ. He lets the reader know that–through faith in Christ–all believers are sons of God. Baptism is the sign of such faith and the public testimony of the transformation. The physical baptism is a sign of the true spiritual baptism that happens at salvation. The results of this transformation is that all cultural, racial, and national barriers are broken down through faith in Christ. There are not jewish Christians versus Greek Christians, no slave Christians versus free Christians, no male of female Christians, just Christians. In Christ, we are Abraham’s seed spoken of by promise in the Word of God. Therefore, we inherit all the promises made to Abraham and live in the blessings of God. The grace of God received through faith is a bongage-breaking, wall-destroying, gender-irrespective force. The social and cultural boundaries that pigeon-hole and restrict us are not present in the spiritual kingdom of God. Instead, the hold of the law (manmade or religious) is broken through grace wrought by faith in Christ.
4:1 Now I say that the heir, as long as he is a child, does not differ at all from a slave, though he is master of all, 2 but is under guardians and stewards until the time appointed by the father. 3 Even so we, when we were children, were in bondage under the elements of the world. 4 But when the fullness of the time had come, God sent forth His Son, born of a woman, born under the law, 5 to redeem those who were under the law, that we might receive the adoption as sons.
Galatians 4:1-7
6 And because you are sons, God has sent forth the Spirit of His Son into your hearts, crying out, “Abba, Father!” 7 Therefore you are no longer a slave but a son, and if a son, then an heir of God through Christ.

Paul, in chapter four, then talks about the status of the believer based upon the image of a slave in the house versus the status of a child in the house. In the time of the writings of Paul things were as such: While the child was young, he was not much different from the slave in the house. His actions and movements were restricted, and he was subject to guardians and stewards who controlled his movements and actions. Only when the father saw fit was the child allowed status and freedom. Paul equates this to the children of God under the law being restricted and bound in the religious system of their time. When Jesus came to die on the cross and rise again to redeem us from the curse of the law, the formerly bound children attained freedom to live out the privileges of a son or daughter. He goes even further to say that as people under the law, they could also be seen as slaves, but through Christ were adopted and made children with privilege. Either way, those once bound were made free and treated as cherished children of the Father. This is victory. This is success. This is joy. Live in the freedom Christ bought for you. Rejoice that in the fullness of time, God sent forth His Son Jesus to redeem us from the curse of the bondage of the law and give us grace and joy!
Artwork from https://storage.googleapis.com/wzukusers/user-26014988/images/5cab51d0989dfQICY8aW/You-are-all-one_d400.jpg and https://www.thefellowshipsite.org/uploads/7/4/1/7/7417809/9795784.jpg?868