Ryken, Leland, James C. Wilhoit and Tremper Longman III, eds.  “Adoption.”  In Dictionary of Biblical Imagery,14-15.  Downers Grove, IL: InterVarsity Press, 1998. [Israel/Christian/Theology/Family]

The five references to adoption in the New Testament, all in the writings of Paul, have great significance because of its conceptual power and “its relationship to many other familial ideas.”  It always refers “to the blessing of God’s people by their heavenly Father.”  The social context apparently does not derive from known Jewish customs of adoption, although the Old Testament does have a “clear sense of God adopting the king” (Ps. 2:6-7; 2 Sam. 7:14).  This adoption of the king “as a representative of Israel may very well lie behind Paul’s use” of the term.  Accepting Christ is the vehicle by which one becomes adopted as God’s people, “in much the same sense as God redeemed Israel and made this people his ‘Son.’” (Hos 11:1)

In the ancient world family membership was “the primary context of social, religious, economic and political security and fulfillment.”  Moving from one family to another was life changing.  In this context adoption communicates “a whole set of nuances of God’s blessings on his people.  “Adoption is listed among the greatest blessings of God upon Israel and Ephesians 1:5 names it as a chief blessing of the Gospel.  It is an “expression of electing love of God which transfers the adopted child from the family of disobedience to the family of God.”