Salvation is also known as deliverance or redemption. It is the salvation of mankind from sin and its consequences including death and separation from God.
Man had a good relationship with God as God could visit him in the Garden for communion. But this didn’t last long, Satan in the form of a serpent one day appeared to Eve in the Garden and deceived her and she ate the forbidden fruit and gave some to Adam. Immediately their eyes opened and they found themselves naked. They tried to hide themselves from God because of guilt.
Therefore, just as through one man sin entered the world, and death through sin, and thus death spread to all men, because all sinned. (Romans 5:12). All men ever born after Adam were born sinners not because of the actions they did but because of the sinful nature of Adam that had spread to all mankind.
Man was heading for eternal destruction in the lake of fire as the scripture says that, For the wages of sin is death (Romans 6:23). No righteous act that man did was enough to save him from destruction. Even his self-righteousness was nothing before the Lord. But we are all like an unclean thing, And all our righteousnesses are like filthy rags; We all fade as a leaf, And our iniquities, like the wind, Have taken us away. (Isaiah 64:6).
All had sinned and fallen short of the glory of God (Romans 3:23) there was none righteous no, not one. There was none who understood, there was none who was seeking after God. They have all turned aside; They have together become unprofitable. None who did good no, not one (Romans 3:10-12).
But God demonstrated His own love toward us, in that while we were still sinners, Christ died for us. (Romans 5:8), This is all by the grace of God through believing in the finished work of Jesus Christ at the cross. Nor is there salvation in any other, for there is no other name under heaven given among men by which we must be saved.” (Acts 4:12). It is only by the name of Jesus Christ that we are saved.
That if you confess with your mouth the Lord Jesus and believe in your heart that God has raised Him from the dead, you will be saved. (Rom 10:9) For “whoever calls on the name of the Lord shall be saved.” (Romans 10:13). When you believe in the name of Jesus Christ you are transferred from the kingdom of darkness to the kingdom of the light of the Son. You receive eternal life and you shall never perish. You are now termed as saved.