Adoption (4b-6): The holy God adopted us.[1] Now, adoption shows we were naturally not His children.[2] This is evident in that we were sinners in need of forgiveness (1:7)—undesirable adoptees! Yet God adopted us. Why? Because He loved us. He did this "in love." In adoption, the holy God brought near to Himself[3] sinners who should have been shunned![4] This revealed "the kind intention of His will" and "the glory of His grace." Further, this was all planned by God. The Father pre-determined His future adoptees, and the Son offered Himself as the mediator and ransom (1 Tim. 2:5-6) to make adoption possible. It was "through Jesus Christ" that we were predestined. The Father planned that we become His sons through the atoning work of His only begotten Son.
Grace (7-8a): God has given us an abundance[5] of His grace, and His Beloved Son[6] is central in all of this. We see this in our redemption.[7] We were released from our sins ("forgiveness ") through the blood of His Beloved, whom the Father deeply cherished. The ransom for our freedom was the death of His only begotten Son! The Father paid dearly to lavish on us His grace. He gave up what was most precious to Him![8] Only spoiled and ungrateful children take precious gifts for granted. May we, instead, like Paul, overflow with praise!
[1] Scripture repeatedly affirms this (Rom. 8:14-17; 2 Cor. 6:17-18; Gal. 4:5-6). Cf. also 1:2; 5:1.
[2] We were actually children of the devil (1 John 3:8-10) and enemies of God (Rom. 5:8-10; Col. 1:21-22).
[3] This adoption was relational. Much like our election (1:4, "before Him"), this was an "adoption… to Himself."
[4] Nearness to God requires that sin first be forgiven (1:7). Isaiah experienced this firsthand (Is. 6:1-7).
[5] "Lavish" is the Greek verb pe-ri-sseu-ō (περισσεύω) which means "to abound." This describes an abundance.
[6] "The Beloved" is a passive participle and it describes Christ as God's Beloved. NET: "in his dearly loved Son." Elsewhere Christ is called the "Beloved," the lover is always the Father (Matt. 3:17; 12:18; 17:5; Col. 1:13).
[7] "Redemption [a-po-lu-trō-sis (ἀπολύτρωσις)]" is the freedom purchased with the payment of ransom.
[8] This payment was infinitely more costly than the best things this world can afford (1 Pet. 1:18-19).