Firstly, our need for adoption into the family of God:
Unfallen Adam was a loyal subject under God’s government and an obedient son in God’s family. When he sinned, he fell from his high position and everything changed....His fall into sin affected him inwardly in his character—he became totally depraved. It also affected him legally—he forfeited all his privileges as God’s son. (3)
"Regeneration is that act of saving grace which, at least incipiently, reimparts to him [the fallen sinner] his lost filial disposition, while adoption is that act of grace which restores to him his filial standing. By the one [regeneration], he is given
the heart of a child, by the other [adoption], he is given the rights of a child. Both are unspeakably important—to have sonship as a law right and prerogative on the one hand, and to have an appropriate filial disposition to correspond to the legal filial status." 2. Webb, The Reformed Doctrine of Adoption, 21. (4)
Adoption, in this redemptive sense, refers to that gracious act of God by which He receives sinners into His family through faith in Christ, and gives them the right to all the privileges and liberties of His children, such as: His Fatherly protection (Ps. 121:7), His Fatherly provision for all our needs (Ps. 34:10), His Fatherly correction
and discipline (Heb. 12:6), His ear to our prayers (1 John 5:14–15), and His wealth as our inheritance (Rom. 8:17). (4)
“But as many as received Him, (Jesus), to them He gave the right to become children of God, even to those who believe in His name” (John 1:12)....Notice the four phrases in this verse. First, “He gave the right.” This privilege of becoming God’s
child is a pure gift of God’s sheer grace....Second, “the right to become.” This statement is concerned with the status of the believer. When he receives Jesus, his
status and legal standing change from that of a hostile rebel to that of a legal heir in God’s family....Third, “children of God.” Not only do God’s children enjoy all the privileges and liberties of sonship, but they also become “partakers of the divine nature” (2 Pet. 1:4). This means that we participate in God’s CHARACTER, not in God’s being. We do not become divine; rather, we become holy, as God is holy....Fourth, “believe on His name.” Adoption into the family of God is through the reception of and belief in Jesus Christ. (5)
A son of God has access to God and fellowship with God. He is also “led” by God’s Spirit. In fact, to be led by the Spirit of God and to be sons of God are interchangeable terms....In this family relationship, the Holy Spirit is fully and necessarily operative. He witnesses to us of the reality of our sonship, thereby
giving us the assurance of it. He guarantees our full possession of our total inheritance as heirs of God in Christ. (7)
“In love He predestined us to adoption as sons through Jesus Christ to Himself according to the [good pleasure] of His will” (Eph. 1:5)....From the context of this verse, we can see that this sonship to which we are predestined includes three blessings: (1) Conformity to the image of God, i.e., we are chosen to holiness of life (vs. 4); (2) Enjoyment of God’s favor, being special objects of His love; and (3) Heirship, i.e., participation in the glory and blessedness of God. Charles Hodge reminds us that “God having predestinated His people to the high dignity and glory
of sons of God, elected them to holiness, without which that dignity could neither be possessed nor enjoyed.” 4. Charles Hodge, A Commentary on the Epistle to the Ephesians (Grand Rapids, MI: William B. Eerdmans Publishing Co., n.d.), 36. (7)
[1] The Fatherhood of God and Forgiveness of Sins: The Fatherhood of God and the forgiveness of sins are so closely connected that one cannot be considered without the other, as illustrated in the parable of the prodigal son and in Matthew 6:14,
15. Forgiveness of sins is the presupposition of the Father-child relationship
between God and Jesus’ disciples. (8)
[2] The Fatherhood of God and the Covenant of God: The origin of the idea of a Father-child relationship in the preaching of Jesus is to be found in the special covenant relationship between Jehovah and Israel in the Old Testament (Ex. 4:22;
Deut. 14:1; 32:6, 18; Isa. 1:2; 63:8–10, 16; Jer. 3:19, 21; 10:20; 31:20; Hos. 11:1, 3; Mal. 2:10). (9)
[3] The Fatherhood of God and Jesus' Messiahship: Jesus taught His disciples to address God as “our Father,” because they are the restored people of God. They are restored to intimate fellowship with God as the redeemed People of the Messiah,
whom Paul describes as “the body of Christ.” (9)
[4] The Relationship Between the Father and Jesus: The real and deepest explanation of this relationship between God and those to whom the kingdom of heaven is promised lies in the person of Jesus Himself; or to put it more accurately, in Jesus’ own relationship with the Father....Jesus never speaks of “our Father,” so as to identify himself with his disciples, but distinguishes between “my Father” and “your Father.” The former expresses the exclusiveness of his Sonship which had
been proclaimed when he entered upon his duties (Matt. 3:17), later confirmed (Matt. 17:5) and therefore always maintained by Him as a special privilege (cf., Matt. 17:24–27).
On the other hand, Jesus is the Mediator with respect to the sonship of believers (Matt. 11:27), “No man knoweth the Son, but the Father, neither knoweth any man the Father, save the Son, and he to whomsoever the Son will reveal him.”...From the character of the gospel it follows that such knowledge is not merely intellectual, but creates a personal relationship (cf. Matt. 7:23). This revelation of the Father by the Son is, therefore, based on the whole of Jesus’ work. It is indissolubly connected with all that he accomplishes for the remission of sins of all those who are his. ....
In fact, He is the Father of Christians precisely because, and only because He is the
Father of Jesus Christ: “Blessed be the God and Father of our Lord Jesus Christ, who has blessed us with every spiritual blessing in the heavenly places in Christ” (Eph. 1:3). God is our Father, because He is Jesus’ Father. (10)
[5] The Fatherhood of God and the Kingship of God: The Fatherhood of God and the Kingship of God are not set over against each other in the preaching of Jesus. Nor is one considered as more important than the other. The fact that God’s Fatherly
relationship with His children, i.e., Christ’s disciples, is connected with His covenant relation with His chosen people as their Sovereign- Friend, indicates the close connection between His Fatherhood and His Kingship. (11)
[6] The Fatherhood of God and the Gift of Obedience: Jesus taught that the doing of God’s will was the proof of citizenship "in the kingdom of God and the proof of adoption into the family of God; but He also taught that doing God’s will was
a gift belonging to the salvation of the kingdom proclaimed by Him.… The truth that obedience to God’s commandments is a gift belonging to the salvation of the kingdom is already clearly implied in the first three petitions of the Lord’s Prayer. The last of them explicitly mentions the doing of God’s will (Matt. 6:10), as a gift that must be asked for of God." 12. Ridderbos, The Coming of the Kingdom, 247. (12)
[7] The Proof of the Sonship of God: Therefore, the doing of God’s will is the norm and standard of sonship to God in His kingdom....Jesus said, “For whoever shall
do the will of My Father who is in heaven, he is My brother andsister and mother” (Matt. 12:50). (13)
[8] Doing God's Will and Fellowship with Christ: "[According to Matthew 7:23,] [i]t is not in a man’s appeal to Jesus, (“Lord, Lord”) on his own authority, but in
Christ’s taking him into his fellowship [knowing him], that we must find the explanation and the criterion of doing righteousness. Outside of this fellowship there is no obedience.…Only those who are known by Him in the sense of this fellowshipwill receive the grace of the doing of the Father’s will (cf. Matt. 13:50)." 15. Ridderbos, The Coming of the Kingdom, 253–54. (13-14)
[9] The Fatherhood of God and the Believer's Life in the World: Jesus taught that the filial relationship His disciples enjoyed with the Father was not only concerned with future bliss in eternity...but also with our temporal life here and now... (14-15)
[10] The Fatherhood of God and Eternal Life: It must be emphatically stated that in Christ’s kingdom, God will be the Father of His disciples-children through all eternity... (15)