Why is redemption through Christ described as adoption?

In Ephesians 1:4-5, we learn that believers are predestined for adoption through Jesus Christ. This imagery of adoption is profoundly comforting, signifying a transition from spiritual death to life as heirs of God's promises. The concept emphasizes that through Christ's sacrifice, believers are not only delivered from the penalty of sin but are also embraced as children of God. This relationship speaks to the heart of grace—believers receive not only forgiveness but also the privileges and joys of being part of God's family, reflecting His love and acceptance.