Let's do something that the scriptures teach, concerning the things that we are to speak, and compare spiritual with spiritual in (1Cor 2:13). We believe the gospel of Jesus Christ to be this; Christ came as was promised in the likeness of sinful flesh to condemn sin in His flesh on the cross. He took upon His body the sin of the world and was judged for that sin through death. He was buried and rose again on the third day. Through His death, burial and resurrection He put away all sin forever. God was in Christ reconciling the world unto Himself not imputing their sins and trespasses unto them, but had imputed them unto His Son, Jesus Christ. Christ was the Lamb that was slain, having all sin transferred to Him, to take away the sin of the world. If we believe this gospel by confessing the Lord Jesus Christ with our mouth and in our heart believe that God raised Him from the dead we shall not perish but have everlasting life.
I think we all agree on that. Now let's compare that to the understanding that we can lose or do something to forfeit the salvation and everlasting life that was promised once we believe. The premise of the gospel is based upon the justice of God that needed all sin to be judged. It would take the blood of a sinless and spotless human sacrifice, offered to God, for sin to be judged and to meet the just demand of a Holy God. Man without God had nothing to do with the plan of God that was executed to judge the sin of man to redeem man from his sin. It was executed without sinful man being involved in any aspect. God's redemption for man was appropriated by God, through God's Son, to redeem man from all sin and be justified to receive God's righteousness by faith. Anything that God did for man could only be received by man though faith, in what God had done for man through Christ.
All the work of God's plan, that provide redemption to man, was executed by God's Son without any work on man's part, thus making redemption God's complete and total work and not man's. Man's part is to believe and receive what God has provided through His Son, Jesus Christ. However, when man believes by faith, man has nothing to do with the salvation that God provides to Him by imputation. It has to be by imputation because it has nothing to do with man being qualified, in any way, to receive it other than being a sinner in need of salvation. That salvation puts us in Christ and seals us with the Holy Spirit, and no man can pluck us out of God's hand (or handiwork). Because we are in Christ, we have been given by the Father to the Son. Jesus said that all the Father has given me none of them are lost (John 17:12, 18:9) and no man can pluck them out of my hand nor my Father's hand (John 10:28,29). So we who believe and are hid with Christ in God (Col 3:3, which is a fixed position that is concealed and locked) have a double protection from the Father and the Son and it is all sealed by the Holy Spirit. All that has been provided by God's grace through faith.
Can man be expected by God to keep and not lose what God judicially provided by grace and through faith, when man could not provide it for himself? If man could keep it, then it would not be by grace nor would it be received by faith. If that is true, man would lose it in a second the first time he failed. There is a lot more to be said but for now that is it.
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