Soli Deo gloria, glory to God alone, was one of the themes of the Protestant Reformation. As that principle worked out in the process of salvation, the focus returned to what God has done for you. As the reformers followed Paul they grasped the centrality of the concept of calling, with justification, adoption, and sanctification flowing out of that union with Christ.
In the Old Testament the focus is not on formal adoption as much as on your status as God’s children. In Exodus 4:22 Moses is to command Pharaoh, “Israel is my firstborn son, and I say to you, ‘Let my son go that he may serve me.’” After the plagues, God led his firstborn son through the desert by the pillar of cloud and fire (and that forms the background for Paul’s emphasis in Romans 8:12-17 that you, as God’s adopted son or daughter, are led by his Spirit. That relationship could be broken but then, by God’s grace, restored, as Hosea 1 and 11 remind you.
As an adopted son or daughter of God remember that you are not in debt to the flesh. The bondage to sin has been broken. Israel in the desert, despite the leading of the cloud, kept being tempted to turn back to the slavery of Egypt. You have not just a cloud, you have the Spirit himself leading you! Follow him!
Romans 8:15 speaks of what happens in you as a believer in Jesus Christ. The Holy Spirit works in you. He enables you to address God as “Abba, Father,” a term that has the closeness of “Daddy,” but also the deep reverence and respect that a child in the Middle East would show to his father. Verse 16 speaks of the testimony of the Holy Spirit to you. Remember that one of the primary ways the Spirit works is by the Word, the Bible.
Being a son or daughter of God involves living as a member of his family, rejoicing in the close fellowship, increasingly reflecting the character of your Father. Appreciate the great privilege you have in being adopted: “The people of God are the sons of God the Father and he sustains to them this highest and most intimate of relationships. This fact enhances the marvel of the relationship established by adoption. The first person of the Godhead is not only the God and Father of our Lord Jesus Christ but is also the God and Father of those who believe in Jesus’ name.” (John Murray, Redemption Accomplished and Applied, p. 139.)
(In preparation for the message on Sunday morning, October 31, 2010)