Answer
A citizen is a person who legally belongs to a country and has the rights and protection of that country. Citizens embrace the culture and customs of the nation or kingdom to which they belong. Every human being is born into the realm of this world, where Satan rules “in whom the god of this world hath blinded the minds of them which believe not, lest the light of the glorious gospel of Christ, who is the image of God, should shine unto them.”, (2 Corinthians 4:4). Consequently, we grow up adopting the culture, customs, and values that he promotes (Genesis 3:1;1 John 2:16).
Satan’s kingdom enslaves its citizens “Know ye not, that to whom ye yield yourselves servants to obey, his servants ye are to whom ye obey; whether of sin unto death, or of obedience unto righteousness?”, (Romans 6:16). With darkened hearts and minds, we blindly follow our leader into the very sins that drag us deeper into slavery. We remain captives in this realm of sin, headed for destruction, until Jesus liberates us (Ephesians 2:1-4). Philippians 3:18–19 emphasizes the distinctions between those who seek communion with Jesus Christ and those who pursue earthly endeavors: “For, as I have often told you before and now tell you again even with tears, many live as enemies of the cross of Christ. Their destiny is destruction, their god is their stomach, and their glory is in their shame. Their mind is set on earthly things.” Those who are unfamiliar with Christ live solely for this world and the pleasures they can secure for themselves. They are “citizens” of this world and conform to it.
As rules and a value system.
When we are born again by faith in Jesus Christ “Jesus answered and said unto him, Verily, verily, I say unto thee, Except a man be born again, he cannot see the kingdom of God.”, (John 3:3), we are born into the Kingdom of Heaven (Matthew 3:2; Matthew 7:21; Romans 14:17). Referring to those who have experienced that spiritual rebirth, Philippians 3:20 states, “Our citizenship is in heaven. And we eagerly await a Savior from there, the Lord Jesus Christ.” Jesus dedicated much of His earthly ministry to explaining the Kingdom of Heaven “From that time Jesus began to preach, and to say, Repent: for the kingdom of heaven is at hand.”, (Matthew 4:17). He likened it to various things, such as a wheat field where weeds grew alongside the wheat. Initially, the plants looked the same, but they were separated during the harvest. The reality is that often the citizens of heaven and those of this world seem indistinguishable, and only God knows the distinction “For the earnest expectation of the creature waiteth for the manifestation of the sons of God.”, (Romans 8:19). Many individuals may seem like citizens of heaven, when in reality, no rebirth has occurred in their hearts “Not every one that saith unto me, Lord, Lord, shall enter into the kingdom of heaven; but he that doeth the will of my Father which is in heaven.”, (Matthew 7:21).
When God bestows upon us citizenship in the Kingdom of Heaven, we become “new creatures” “Therefore if any man be in Christ, he is a new creature: old things are passed away; behold, all things are become new.”
, (2 Corinthians 5:17). He sends His Holy Spirit to indwell our spirits, and our bodies become His temple (1 Corinthians 3:16;1 Corinthians 6:19-20). The Holy Spirit begins to transform our sinful, worldly desires into those that glorify God (Romans 12:1-2). His goal is to make us as much like Jesus as possible in this life «For whom he did foreknow, he also did predestinate to be conformed to the image of his Son, that he might be the firstborn among many brethren. », (Romans 8:29). We are given the power and privilege of exiting the world’s flawed value system and living for eternity (1 John 2:15-17). To be adopted into the family of God means that we become citizens of an eternal kingdom where our Father is the King. Our focus turns toward eternal things and storing up treasure in heaven (Matthew 6:19-20). We consider ourselves ambassadors to this earth until our Father sends for us and we go home (Ephesians 2:18-19;6:20).
We live for a short time in these physical bodies, anticipating the bright future in our real home. While here, we share Abraham’s experience, living “like a stranger in a foreign country. . . looking forward to the city with foundations, whose architect and builder is God” (Hebrews 11:9-10).