Galatians 4

Paul uses the analogy of a child heir to explain Christian liberty. Before Christ, believers were like children under strict guardianship (the Law). Now, through faith in Christ, we are adopted as adult sons and daughters and receive the Spirit of God, who enables us to cry out, "Abba, Father." Paul uses the allegory of Sarah (freedom) and Hagar (slavery) to contrast the New Covenant based on promise with the Old Covenant based on Law-keeping.