You must be born again

Marvel not [do not be surprised, astonished] at My telling you, you must all be born anew (from above).

–  John 3:3

The following three verses explains the Gospel so clearly. John 3 verse 16-18: “For God so greatly loved and dearly prized the world that He [even] gave up His only begotten (unique) Son, so that whoever believes in (trusts in, clings to, relies on) Him shall not perish (come to destruction, be lost) but have eternal (everlasting) life. 17 For God did not send the Son into the world in order to judge (to reject, to condemn, to pass sentence on) the world, but that the world might find salvation and be made safe and sound through Him. 18 He who believes in Him [who clings to, trusts in, relies on Him] is not judged [he who trusts in Him never comes up for judgment; for him there is no rejection, no condemnation—he incurs no damnation]; but he who does not believe (cleave to, rely on, trust in Him) is judged already [he has already been convicted and has already received his sentence] because he has not believed in and trusted in the name of the only begotten Son of God. [He is condemned for refusing to let his trust rest in Christ’s name.]  2 Cor 5 verse 18-20 says, “But all things are from God, Who through Jesus Christ reconciled us to Himself [received us into favor, brought us into harmony with Himself] and gave to us the ministry of reconciliation [that by word and deed we might aim to bring others into harmony with Him].19 It was God [personally present] in Christ, reconciling and restoring the world to favor with Himself, not counting up and holding against [men] their trespasses [but cancelling them], and committing to us the message of reconciliation (of the restoration to favor). 20 So we are Christ’s ambassadors, God making His appeal as it were through us. We [as Christ’s personal representatives] beg you for His sake to lay hold of the divine favor [now offered you] and be reconciled to God.”  From God’s side you are reconciled, but the same chapter says, “BE RECONCILED.”   

Christianity is completely inclusive because Jesus died for all, but also completely exclusive, because only those who believe in Him are in Christ, have died with Christ, were raised with Christ, are seated with Christ, are born again, are saved, are righteous, are holy, are sanctified, are called children of God, are called saints, are called believers, are called Christians. So, unless you walk in by choice, you are still outside. Everyone is not just automatically saved. If the family of Noah did not decide to go into the ark, they would have died in the flood. There are some that say that Christ is already in all people and that they must simply awaken to the fact that He is in them. This statement, the fact that we need to awaken to the truth that Christ is in us, is completely true for people that have accepted Christ, but it is absolutely not true for those who have not received Jesus as their Saviour. Jesus did not tell the Pharisees that they were all saved. No! He said to them “you are of your father the devil, because my words do not find entrance into your hearts.” (John 8:44-47). When you are born again you have received a complete new nature (2 Corinthians 5:17), and this nature is completely different from your old nature or from the nature of unbelievers. 1 Peter 1:23: “You have been regenerated (born again), not from a mortal origin (seed, sperm), but from one that is immortal by the ever living and lasting Word of God.” When His words found entrance into our hearts the first time, we got born again.

If you preach the Gospel, you tell people about what Jesus Christ did for them (all people). For some the words find entrance into their hearts and they are saved/ born again/ born from above.

Inclusive, because everyone was included in the price that was paid.

Exclusive, because only those who received Him, have the authority to become the children of God. They are part of the household of God and God is THEIR Father.