Two great quotes you have seen before are repeated because of their importance. Each quote emphasizes the essential nature of Union with Christ.
“Nothing is more central or basic than union and communion with Christ. … Union with Christ is in itself a very broad and embracive subject … Union with Christ is really the central truth of the whole doctrine of salvation not only in its application but also in its once-for-all accomplishment of the finished work of Christ. Indeed the whole process of salvation has its origin in one phase of union with Christ.”
John Murray – Redemption Accomplished and Applied, p. 171-172, Eerdmans, 1955
“The first effect of faith, according to Scriptures, is union with Christ” (p.104). “The proximate effect of this union, and consequently, the second effect of faith is justification” (p. 105).
Charles Hodge – Systematic Theology, Vol. 3
Christ’s redemptive activity paid the price for each believer’s salvation in its entirety. The salvation purchased by Christ is applied by the Holy Spirit to elect (but spiritually dead) sinners. The key concepts involved in the Holy Spirit’s application of the benefits of salvation are given in Westminster Shorter Catechism answers to Questions 29-32 which were cited in Part 11.
The Holy Spirit works faith in believers, thereby uniting them to Christ in effectual calling. Being united with Christ is the first effect of faith. This work of the Holy Spirit enables believers to repent from sins and to recognize and accept Christ, the only basis for their salvation. The second effect of faith is the act in which the Father declares the new believer to be justified (legally righteous) before Him. Justification is a legal declaration by God (through grace based on faith alone). The believer’s sins are forgiven. Christ’s righteousness is imputed to them.
The moment sinners believe in Christ, God forgives their sins and declares them righteous before the Law (pardons them), brings them into His family by adoption, and seals them to the day of redemption with the indwelling Spirit of adoption. While we view these as logically separable events, there is no time delay involved between them.
The next element in the chain of events constituting salvation is that redeemed sinners, now properly called Christians, begin a process of progressive sanctification not ending until mortal death. During the progressive sanctification process, Christians, by the power of the Holy Spirit, persevere and increase in holiness. At mortal death, soul and body separate. The body returns to the earth and the soul is glorified (made completely holy) and returns to God. There remains one final step. Christ redeems both body and soul. The unification of the glorified soul with a glorified resurrection body completes the process. That occurs when Christ returns to earth in power and glory. At that point Christians are fully conformed to the image of the Son of God. Their Union with Christ endures through it all.
Adoption – God’s Great Gift of Grace
Like justification, adoption into God’s family is a legal judicial work of God. Adoption, while distinct from regeneration and justification, is never separate from them. Believers are passive as God regenerates and bestows justification and adoption. During the process of progressive sanctification, believers actively participate (in a secondary role) as enabled by the Holy Spirit. Justification and adoption into God’s family occur simultaneously.
This is an incredible manifestation of God’s love and mercy to His people. Rather than subjecting sinners to His wrath as they justly deserve, God elected them to salvation. Predestined by God to be children of God, they are adopted into His family through Jesus Christ. This has always been God’s plan. The Son of God, eternally begotten by the Father, is unique. Not even the Holy Spirit is related to the Father in the same sense. Believers are adopted. Adoption into the family of God as part of His saving grace, establishes a Father-child relationship of love and care on the part of the Father, and a relationship of faithful obedience and love on the part of the adopted child. Adopted children of God are co-heirs with Christ.
“even as he chose us in him before the foundation of the world, that we should be holy and blameless before him. In love 5 he predestined us for adoption to himself as sons through Jesus Christ, according to the purpose of his will, 6 to the praise of his glorious grace, with which he has blessed us in the Beloved.”
Ephesians 1:4-6
To be made righteous in the sight of the law (justified) is entirely different from being received into the house of the Father as His adopted children (adoption).
If Adoption by God is Necessary, Then We Are Not Naturally in His Family: This truth is opposed to the cultural mindset in which all people are considered to be children of God. All people are creatures of God, but fallen humanity is not in God’s family. The family of God is composed of the redeemed.
To adopt someone is to make that person a legal son or daughter. Jesus came “to redeem those who were under the law, so that we might receive adoption as sons” (Galatians 4:5). He came so that we might be adopted by God. God does, as He planned, adopt us into His family through Christ: “For you did not receive the spirit of slavery to fall back into fear, but you have received the Spirit of adoption as sons, by whom we cry, ‘Abba! Father!’” (Romans 8:15).
Adoption was uncommon among the Jews. A person’s identity and standing was based on their birth. For that reason, if a man died without a son, his brother was supposed to marry the widow. The first-born son of that new marriage was to be legally considered the son of the dead brother so that his family line would continue. In John 3, Jesus speaks to Nicodemus, a Jewish leader, and uses the Jewish concept of being brought into God’s family by being born again.
On the other hand, for the Romans, adoption was common practice. Today, we can write a will and leave wealth and property to anyone we choose, male or female. In the Roman world, with few exceptions, a man was required to pass his wealth on to his son(s). A man with no sons or no sons he believed to be worthy or capable of managing his wealth, could adopt someone he believed would be a worthy son. The ones adopted were usually older boys and adult men of proven “worth.” After legal approval, the adoptee received a new name, his debts were cancelled, and he became the legal son of his adoptive father, entitled to all rights and benefits of a son plus one thing. It was possible for a father to disown a natural-born son, but adoption was irreversible
As Paul wrote to the Roman churches, he spoke of adoption in terms familiar to the Romans. “I mean that the heir, as long as he is a child, is no different from a slave, though he is the owner of everything, 2 but he is under guardians and managers until the date set by his father. 3 In the same way we also, when we were children, were enslaved to the elementary principles] of the world. 4 But when the fullness of time had come, God sent forth his Son, born of woman, born under the law, 5 to redeem those who were under the law, so that we might receive adoption as sons. 6 And because you are sons, God has sent the Spirit of his Son into our hearts, crying, “Abba! Father!” 7 So you are no longer a slave, but a son, and if a son, then an heir through God” (Galatians 4:3–7). Christians, like all humans, are born enslaved to their sin nature, but Christ paid the price to free us from that slavery. We are justified by the Father, receive the indwelling Spirit, and adopted by God, becoming heirs.
In the Roman world, women could not normally receive an inheritance. However, Paul, carefully points out that, through Christ, both men and women have been adopted and both receive full legal rights. A woman could not be an heir of a Roman father, but a believing woman is an heir of God.
When the Holy Spirit works faith in us, thereby uniting us to Christ, we receive justification before God and are adopted into God’s family. The penalty due our sins is cancelled, we receive a new name (Christian), and are entitled to all the rights possessed by heirs of God.
Roman practice was to adopt a worthy heir. God adopts totally unworthy people who were at enmity to Him. Grounded in His love, grace, and Christ’s redemptive work, God saves and adopts us in spite of our unworthiness. From the Jewish perspective, Christians were “born again” into God’s family. From the Roman perspective, Christians were adopted into God’s family. The result is the same from either perspective. Christians, redeemed from the fallen family of Adam by Christ’s work, enter into the eternal family of God, their Father.
Scripture teaches that mankind is divided into two categories, e.g., John 8:38-44; Matthew 13:36-43; 1 John 3:10-12. (1.) Those adopted into God’s family as a result of faith in Christ. Through God’s grace, these people are in Union with Christ and God is their Father. (2.) Those outside of Christ, not in Union with Christ.
Significance of Adoption
The Holy Spirit works faith in those being redeemed, thereby uniting them with Christ. The next step is the Father’s declaration of their legal righteousness before Him. The justified believer receives the indwelling Spirit certifying the forgiven sinners legal standing before God. The added blessing of adoption is of great significance, denoting family ties, establishing a deep loving relationship with God our Father. Believers become His children and heirs, drawn together in intimate fellowship. The relationship is close, affectionate, and generous. As J.I. Packer says in his book, Knowing God, having right standing before God the judge is essential, but the gift of being loved and cared for by God the Father is even more astounding.
Only people who believe in Christ become children of God. John 1:12-13: “But to all who did receive him, who believed in his name, he gave the right to become children of God, 13 who were born, not of blood nor of the will of the flesh nor of the will of man, but of God.” The sequence is that a person is born of God through the Holy Spirit’s working faith in them, thereby uniting them to Christ. As a consequence of exercising the “worked-in” faith to believe in Christ, that person is justified and adopted into God’s family.
As part of salvation, when God adopts a person, He removes them from the kingdom and spiritual family of Satan and gives them new citizenship in His own kingdom as members of His own family. Philippians 3:20-21: “But our citizenship is in heaven, and from it we await a Savior, the Lord Jesus Christ, 21 who will transform our lowly body to be like his glorious body, by the power that enables him even to subject all things to himself.”
Adoption Provides a Foundation for Christian Living
Being adopted into God’s family and privileged to have a Father-child relationship with God is a strong foundation for life in Christ. Romans 8:14-17: “For all who are led by the Spirit of God are sons of God. 15 For you did not receive the spirit of slavery to fall back into fear, but you have received the Spirit of adoption as sons, by whom we cry, “Abba! Father!” 16 The Spirit himself bears witness with our spirit that we are children of God, 17 and if children, then heirs—heirs of God and fellow heirs with Christ, provided we suffer with him in order that we may also be glorified with him”.
“Abba” is an intimate Aramaic term indicating a believer’s close relationship with the Father. The spirit of slavery as mentioned seems to be obedience to the moral Law motivated by fear of punishment. That kind of obedience never really works and is not what is required. What is required is that obedience be through a child-like love of righteousness aimed at pleasing our heavenly Father. That kind of true obedience is only possible for the redeemed.
John gave important truths concerning adoption and how it relates to Christian living in 1 John 3:1-3: “See what kind of love the Father has given to us, that we should be called children of God; and so we are. The reason why the world does not know us is that it did not know him. 2 Beloved, we are God’s children now, and what we will be has not yet appeared; but we know that when he appear we shall be like him, because we shall see him as he is. 3 And everyone who thus hopes in him purifies himself as he is pure.” John speaks of God’s tremendous love demonstrated by God in adopting believers into his family. He also reminds believers to not be surprised when the world dislikes them. The world also disliked Christ. The more we are like Christ, the more we will encounter dislike.
The next thought is that even though believers know they are God’s children, they do not know the full extent of the salvation God has prepared for them. They do know from Scripture that they will be like Him when they see Him as He is. Finally, everyone, who shares this hope in Christ by having been adopted into God’s family, strives to live in an obedient way, purifying themselves, as they honor Him who saved them through His own life and painful death. Live for Christ as He died for those to be redeemed. He has prepared for believers a future so marvelous it cannot be described in human terms.