Some people say, “Once saved, always saved,” This theology is totally wrong. You have to follow the teaching the Bible. Not the doctrine created by men. Especially when it is wrong. You have to follow Jesus, carrying your cross every day. Some say we are saved by faith, and while that’s true, the definition of faith includes daily obedience to the commandments and teachings of Jesus and the Bible. So what is the commandment? It is loving God and loving your neighbour as yourself. The Faith must also be accompanied by repentance. Repentance is not just saying “I’m sorry”; it involves turning away from sin completely. So the faith includes all those factors.
What is Sin?
The main sin is not accepting Jesus Christ as Lord for our daily life. Bible keeps emphasizing this points over and over. If you don’t have Jesus in your heart, you gain nothing. When you pray, you have to pray for Jesus. You have to ask Jesus to be your Lord over your life.
Sin as Disobedience to God
The Bible first introduces sin in Genesis 3, where Adam and Eve disobey God by eating from the tree of the knowledge of good and evil. This act of disobedience is seen as original sin of all human beings, and it reflects the broader biblical theme that sin is fundamentally rebellion against God.
Now let’s check Bible verses together.
Genesis 2:16-17:
And the Lord God commanded the man, ‘You are free to eat from any tree in the garden; but you must not eat from the tree of the knowledge of good and evil, for when you eat from it you will certainly die.’”
Here, sin enters the world through a refusal to follow God’s command, leading to the separation of humanity from God. This idea is expanded upon later in the Bible, where sin is often depicted as turning away from God and His will.
Sin in the New Testament is Rejecting Jesus Christ which is equivalent to not believing the love of Jesus Christ.
In the New Testament, the concept of sin becomes closely connected with one’s relationship to Jesus Christ. The most serious sin is rejecting Jesus, as He is the way to eternal life.
John 3:16-18:
“For God so loved the world that He gave His one and only Son, that whoever believes in Him shall not perish but have eternal life. For God did not send His Son into the world to condemn the world, but to save the world through Him. Whoever believes in Him is not condemned, but whoever does not believe stands condemned already because they have not believed in the name of God’s one and only Son.”
This passage highlights that believing in Jesus is the key to salvation. The sin of not believing in Jesus condemns a person because they reject the only path to eternal life. The implication is that rejecting Jesus is rejecting God’s plan for salvation.
John 14:6:
“Jesus answered, ‘I am the way and the truth and the life. No one comes to the Father except through me.’”
This verse reinforces that Jesus is the only way to have a relationship with God and receive salvation. Not accepting Him as Lord excludes one from being reconciled with God.
The Role of the Holy Spirit and Conviction of Sin
Jesus taught that the Holy Spirit would convict the world of sin, specifically the sin of not believing in Him.
John 16:8-9:
“When He (the Holy Spirit) comes, He will prove the world to be in the wrong about sin and righteousness and judgment: about sin, because people do not believe in me.”
Here, Jesus is speaking about the work of the Holy Spirit, who will convict people of their greatest sin — not believing in Jesus. This shows that the refusal to accept Jesus as Savior and Lord is considered the ultimate sin in the New Testament.Faith in Jesus Brings Salvation
Paul emphasizes throughout his letters that faith in Jesus is the foundation for salvation, and not having this faith means remaining in sin.
Romans 10:9:
“If you declare with your mouth, ‘Jesus is Lord,’ and believe in your heart that God raised Him from the dead, you will be saved.”
This verse makes it clear that salvation requires both confession that Jesus is Lord and genuine belief in His resurrection. Without this faith, one cannot be saved and remains in sin.
Acts 4:12:
“Salvation is found in no one else, for there is no other name under heaven given to mankind by which we must be saved.”
The apostles clearly state here that salvation is only possible through Jesus. Rejecting Him is not just another sin — it is the sin that keeps one from entering into salvation.
Eternal Consequences of Rejecting Jesus
The Bible also speaks about the eternal consequences of rejecting Jesus as Lord.
2 Thessalonians 1:8-9:
“He will punish those who do not know God and do not obey the gospel of our Lord Jesus. They will be punished with everlasting destruction and shut out from the presence of the Lord and from the glory of His might.”
Rejecting the gospel of Jesus Christ leads to eternal separation from God, which is the ultimate consequence of sin. Here, not obeying the gospel is equivalent to not accepting Jesus as Lord.
Conclusion: Jesus as the Foundation of Salvation
In the Bible, sin is primarily seen as separation from God, and in the New Testament, this separation is defined by one’s relationship with Jesus Christ. Accepting Jesus as Lord is the only way to restore a right relationship with God. Therefore, the gravest sin in the Christian worldview is the refusal to accept Jesus as Lord and Savior.
Rejecting Jesus isn’t just seen as a passive act but an active form of disobedience against God’s offer of salvation. This is why, in Christian theology, the decision to not follow Jesus is considered the central and most serious sin.