Ephesians 2:19 advances Paul's picture of believers from fellow citizens of a state to members of God's household, a more intimate, internal, personal, blood-based relationship rather than a general, external, legal, and impersonal one. Having been by nature children of wrath, Christians are not merely forgiven but adopted into the family of God, like the prodigal son restored as a son rather than a servant. This is true only through Jesus Christ, the Firstborn among many brethren and elder brother, who is Advocate and Intercessor; no one belongs to the family apart from Him and obedience to the Father's will. Adoption brings privileges: God is Father, so His children have confident access to Him, as a busy executive drops everything for his toddler's knock, and they are heirs and joint heirs with Christ, to be glorified personally rather than depersonalized. Because the world, under Satan, depersonalizes people, the church is to be a personal family rather than a corporation. Membership also carries responsibility: children must reflect the Father through good works, loyalty, and faithfulness, asking whether an action is worthy of the Father's Son, remembering that they are no longer strangers or foreigners but members of the household of God.

Conversion is likened to an immigrant's assimilation into a new homeland. Baptism is like taking the oath of citizenship: at that point believers pledge allegiance to Christ as King and are reckoned citizens of heaven (Philippians 3:20). Yet, like first-generation immigrants who keep their old accent, food, and customs, new converts still look like the old country, and it takes a lifetime to take on the traits of the godly and be transformed into the image of Jesus Christ. Conversion, from the Greek strefo and Hebrew shub, means a complete turning around of one's whole way of life, not only a change of mind (metanoia), and it is initiated and maintained by God's grace, as the passive form in Matthew 18:3 shows. Conversion also recurs in episodes, since believers fall away and need to be turned back, as David did in Psalm 51. People are converted unevenly across different areas of sin, so a member who stumbles should not be condemned as unconverted. The man disfellowshipped in Corinth was restored and welcomed back with love. Assimilation into the spiritual family therefore calls for patience, gentle restoration of the fallen, and bearing one another's burdens (Galatians 6:1-2) while all are being transformed.

The source treats assimilation into the spiritual family only briefly, as part of the third cost of discipleship: the Christian life demands new loyalties. Drawing on Luke 9:57-62, where a would-be follower wants to say farewell to those at his home, it notes that many Christians are the only ones called from their families. Over time they find they have little in common even with their own blood, because the way of life diverges so sharply. In the church, however, they find a new family, a new identity, a new purpose, and a new way of life. Although blood ties are strong, Jesus warns that devotion to Him and to God's family must be stronger. This is not automatic, since the Holy Spirit does not simply infuse total commitment. It is an act of will, in which a person sets God as first priority and goes where He says. Anyone who puts a hand to the plow and looks back is not fit for the Kingdom. II Timothy 2 reinforces the point: a soldier does not entangle himself in the affairs of ordinary life but serves the One who enlisted him.