“The law was our schoolmaster to bring us unto Christ, that we might be justified by faith.” – Galatians 3:24

And because ye are sons… – Galatians 4:6

An unjustified man stands in the condition of a criminal, not of a child: his sin is laid to his charge, he is reckoned as unjust and unrighteous, as indeed he really is, and he is therefore a rebel against his king, and not a child enjoying his father’s love. But when faith realizes the cleansing power of the blood of atonement, and lays hold upon the righteousness of God in Christ Jesus, then the justified man becomes a son and a child. Justification and adoption always go together. “Whom He called them He also justified,” and the calling is a call to the Father’s house, and to a recognition of sonship. Believing brings forgiveness and justification through our Lord Jesus; it also brings adoption, for it is written, “But as many as received Him, to them gave He power to become the sons of God, even to them that believe on His name.”

“After that faith is come, we are no longer under a schoolmaster.” When we groaned under a sense of sin, and were shut up by it as in a prison, we feared that the law would punish us for our iniquity, and our life was made bitter with fear… but now that faith has come we see the law fulfilled in Christ, and ourselves justified and accepted in Him: this changes the slave into a child, and duty into choice. Now we delight in the law, and by the power of the Spirit we walk in holiness to the glory of God. Thus it is that by believing in Christ Jesus we escape from Moses, the taskmaster, and come to Jesus, the Saviour; we cease to regard God as an angry Judge and view Him as our loving Father. The system of merit and command, and punishment and fear, has given way to the rule of grace, gratitude, and love, and this new principle of government is one of the grand privileges of the children of God. ~ C.H. Spurgeon

https://www.blueletterbible.org/Comm/spurgeon_charles/sermons/1435.cfm