Theological question on FB: “If a Christian Believer is Already Saved, why is Ongoing Repentance Necessary?”
Repentance of sin seeking forgiveness in the life of the believer is necessary because even though we are “born again” by the Spirit of God by grace through faith in Jesus as our Lord and we have received the indwelling Holy Spirit as the Seal and Guarantor of relationship with God the Father, we remain encumbered by a body of sinful, decaying, flesh that struggles with our new-nature in the Spirit (Romans 7). A Christian, as they walk with the Spirit in the life-long process of sanctification will, especially early in their Christian walk, struggle with certain sins and will possibly sin against the God we love either by omission or commission; therefore, the faithful in Jesus Christ ask forgiveness for sin NOT to reestablish their salvation that is secure in the Spirit forever (John 10:28-30) but the faithful repent of their error and ask forgiveness (1 John 1:9) in order to reestablish intimacy with our Lord.
Understand, it is sin that creates a chasm between the Lord and mankind; Jesus Christ bridged that chasm for us as He suffered and died to pay our sin-debt and reunited God the Father and mankind through His own blood thereby establishing peace with God for everyone who trusts in Christ as Lord (Romans 5:1).
That same sin in the life of the believer, though it does not create a void in our salvation with God, the sin of a believer does interrupt intimacy and grieves the Holy Spirit that dwells within us; therefore, when we repent of our sin and ask forgiveness, we are seeking restored intimacy with our Lord which is second only in value to our salvation. It is intimacy with our God that makes life worth living and brings peace and assurance in our daily walk; therefore, the faithful are careful to walk in obedience and enjoy fully our relationship of love with our God. Having tasted the love of God through the Spirit, the believer knows that nothing greater exists within the Realm of Time (John 15:11; Nehemiah 8:10).