There is a difference between justification which follows regeneration and faith, and sanctification. Justification is a legal act of divine grace, affecting the judicial status of man, and sanctification is as a moral or re-creative work, changing the inner nature of man. Yet there is an inseparable connection between the two. While man is justified by faith alone, the faith which justifies is not alone. Justification is immediately followed by sanctification, since God sends out the Spirit of His Son into the hearts of His elect as soon as they are justified, and that Spirit is the Spirit of sanctification.
We say that man takes part in the work of sanctification. This does not mean that man is a free agent in the work, so as to make it partly the work of God and partly the work of man. Sanctification is a work of the triune God, but is attributed more specifically to the Holy Spirit in Scripture (Romans 8:11; Romans 15:16; I Peter 1:2). Instead we mean that God effects the work in part through the instrumentality of man as a rational being, by requiring of man prayerful and intelligent cooperation with the Spirit. That man must cooperate with the Spirit of God is clear from (a) the repeated warnings against evils and temptations, which clearly imply that man must be active in avoiding the pitfalls of life (Romans 12:9; Romans 12:16-17; I Corinthians 6:9,10; Galatians 5:16-23); and (b) the constant admonishments to holy living. These imply that the believer must be diligent in the employment of the means at his command for the moral and spiritual improvement of his life, Micah 6:8; John 15:2,8,16; Romans 8:12-13; Romans 12:1,2,17; Galatians 6:7-8; Galatians 6:15.
We need also understand that the commandments given in Scripture serve a purpose for the perseverance of the saints.
Believers are not mere punctiliar Christians. The Spirit waters and feeds our repentance and faith through the means of grace. These means keep us alive in the faith and are not just a means for starting us in the faith. God commands our ongoing attention to our faith, with daily Scripture study, prayer, fellowship with others, and regular assembly with others to worship God, through which we examine ourselves to make sure our faith is real. God also provides that which He commands, ordaining the ends as well as the means to the ends, even the believer's salvation. Augustine's little prayer sums it up: "O Lord, grant what Thou dost command and command what Thou dost desire." Pelagius never grasped what Augustine meant, failing to see that no one can please God unless God helps us in some manner to meet His requirements.
As Scripture teaches, enduring to the end, holding fast to the faith, abiding in Christ and His Word are essential to one's salvation. If these do not exist a professing Christian cannot expect to be saved.
But, and this is important, some hold that a true believer may not persevere and can be ultimately lost. Instead I believe, along with the Reformers, that the true believer will in fact persevere. At this point, some would then ask, "Well, if the believer will persevere then why do the Scriptures contain admonitions or conditions for salvation?" In reply I answer, as noted above, God ordains the end but also the means to the end.
One of those means of God to His final glory is the perseverance of the Christian in faith to the end. I understand that one way God effects this means of perseverance in the saved is by admonishing them of the consequences of not persevering to the end and the conditions for salvation. I take these admonishments seriously. These admonishments stir up the faithful.
An example might help explain this. Consider Paul about to be shipwrecked in Acts 27. We read that God had assured Paul that no one would lose their life in that shipwreck. Yet, despite this clear assurance from God, Paul admonishes those on the ship that unless the persons trying to leave by the lifeboat remain on board, those on the ship would not be saved. Note here that the Apostle was assured of their salvation, he knew the means of their salvation, and his warning produced the desired result.
Speaking under the inspiration of the Spirit, Peter tells us that those who are "elect according to the foreknowledge of God" and "begotten again unto a lively hope" are "kept by the power of God through faith unto salvation ready to be revealed in the last time." (I Peter 1:2-5).
Indeed, God's almighty power preserves the true believer so that he or she receives that final and complete salvation that will be revealed at the Eschaton. It can be no other way, for the work of salvation (the entire Golden Chain of redemption) is God's work and God's work does not fail.
