Justification is just one facet of salvation. The underemphasis of justification (legalism) and overemphasis of justification (antinomianism) are only parts of the slippery slope leading to error. Legalism and antinomianism are also both detrimental to the other important facet of salvation that coincides with justification, the sanctification process. The root of the word “sanctification” is sanctify, which means “to make holy.” Succinctly, sanctification is the process initiated by God to conform the believer progressively into the image of Christ. It is “the continuing of God’s grace by which the Christian may constantly grow in grace and in the knowledge of our Lord Jesus Christ.” “God making us more and more righteous in ourselves” is how Ferguson pithily defines sanctification.
The Purpose of Sanctification
Sanctification’s design is “to change our thoughts, words, and actions into the likeness of Christ and to so change our basic inner nature that these thoughts, words, and actions represent a real attitude of heart.” In other words, sanctification is about change that progressively occurs throughout a process of growth with the ultimate goal of being conformed to the likeness of Christ. No matter the growth of a believer in the sanctification process, without a continual change toward Christ-likeness there is no sanctification. This is why the telos, or goal, must be clearly understood during the sanctification process. Porter is correct to suggest that legalism is a possible outcome if the telos is not implicit. He states, “There is no easier path to works righteousness and legalism than to have a mistaken or confused notion of the goal of spiritual growth.” The legalist and the antinomian either do not completely understand the goal, or the goal is completely ignored for egocentric reasons. The telos, however, is “holiness,” “Christlikeness,” or “moral transformation.” Understanding these as the goal of sanctification should eliminate much of the confusion surrounding the purpose of sanctification. When the purpose is properly understood the process will likely take place more efficiently. This in turn should minimize the propensity of the heart to succumb to the devastating effects of legalism and antinomianism as they distort sanctification.
Sanctification as a Process
Sanctification is a process as it entails past, present, and future aspects of holiness. Despite the differing views of sanctification in Protestant evangelical circles, all major views agree that sanctification is a process that exists in these three time frames. Gundry elaborates on these aspects when he explains sanctification “is past because it begins in a position of separation already gained in Christ’s completed work. It is present in that it describes a process of cultivating a holy life. And sanctification has a future culmination at the return of Christ, when the effects of sin will be fully removed.” These three time frames that sanctification takes place in are usually classified as initial (past tense), progressive (present tense), and final (future tense) sanctification. However, a distinction needs to be made. On the one hand, a believer’s spirit will be completely sanctified at the time of death. At that time, the believer will no longer be susceptible to sin’s influence. On the other hand, sanctification will not be “completed” until the second advent of Christ during the eschaton when the physical remains of a believer in the grave will be transformed and reunited with the believer’s spirit. God sees to all of these details. However, where legalism and antinomianism can short circuit sanctification originates in the believer’s role in the process.
God’s Role in Sanctification
Ultimately, “Sanctification is not moral action on the part of man, but a divinely effected state.” It is a work of God. It is God who brings about holiness in his people. The Holy Spirit is the member of the Godhead who accomplishes all aspects of sanctification in a believer whether it is initial, progressive, or final sanctification. No amount of human work can reach the goal of Christ likeness. Only God can bring about the result of this task by the influence of the Holy Spirit in the life of a submissive believer.
The Believer’s Role in Sanctification
The believer also has a role in sanctification. God surely has complete control over the whole sanctification process. Without God’s involvement no believer could be sanctified. However, the believer must be submissive to God’s influence allowing God to perform his work of sanctification. How this is accomplished is through obedience to biblical teaching by performing good works, living in holiness, and remaining compliant to the Spirit throughout the process. When the believer obeys, God is allowed to perform his work of sanctification within the believer. Essex concisely reveals what the human part of the sanctification process should look like in an obedient believer’s life when he states,
The positionally sanctified believer will evidence a growing godliness and Christ-likeness as he learns and obeys Holy Scripture enabled by the Holy Spirit. This obedient life-style is the visible “fruit” of progressive sanctification. This progressive sanctification will culminate in his completed sanctification when Jesus Christ appears and he is transformed into His likeness (1 John 3:2); then, growing Christ-likeness will become total Christ-likeness in character.
 Louw and Nida, Lexicon, 744.
 Rom 8:29; 1 Thess 5:23; 2 Cor 7:1; 2 Pet 3:18; Heb 6:1; 1 John 1:7, 9, 5:4; Col 4:12; Prov 4:18; 1 Pet 1:16; Gal 2:20.
 Treatise of the Faith and Practices of the National Association of Free Will Baptists (Nashville: National Association of Free Will Baptists, 2013), 12.
 Sinclair B. Ferguson, Devoted to God: Blueprints for Sanctification (Carlisle: Banner of Truth, 2016), 9.
 Forlines, Arminianism, 283.
 Forlines identifies two different, but connected categories within sanctification: positional and experiential sanctification. He states, “We are positionally set apart by God at conversion. We are experientially sanctified only as we practice holiness.” (Forlines, Arminianism, 281).
 Steven L. Porter, “On the Renewal of Interest in the Doctrine of Sanctification: A Methodological Reminder,” JETS 45/3 (September 2002): 416.
 Ibid, 417.
 Stanley N. Gundry, Five Views on Sanctification, Zondervan Counterpoints Series (Grand Rapids: Zondervan, 1987), 7. The five major views of sanctification adopted by evangelical Christians today are the (1) Wesleyan Perspective, (2) Reformed Perspective, (3) Pentecostal Perspective, (4) Keswick Perspective, and (5) Augustinian-Dispensational. For more on these views see (Gundry, Five Views on Sanctification).
 Initial sanctification is also referred to as “positional” or “definitive” sanctification.
 Progressive sanctification is also referred to as “experiential” sanctification.
 Final sanctification is also referred to as “glorification.”
 Forlines, Arminianism, 282.
 Gerhard Kittel, Geoffrey W. Bromiley, and Gerhard Friedrich, Theological Dictionary of the New Testament (Grand Rapids: Eerdmans, 1964), 112.
 Phil 2:13.
 Phil 2:12.
 Spiritual disciplines are a vital way for the believer to promote and maintain holiness. For more see Jerry Bridges, The Discipline of Grace: God’s Role and Our Role in the Pursuit of Holiness. Colorado Springs: NavPress, 2006; Donald S. Whitney, Spiritual Disciplines for the Christian Life. Colorado Springs: NavPress, 1991.
 God “working in” the believer, and the believer “working out” their own salvation is the paradox that Paul described in Phil 2:12-13. He is describing the responsibilities of both God and man in sanctification.
 Keith H. Essex, “Sanctification: The Biblically Identifiable Fruit,” MSJ 21/2 (Fall 2010): 212-13.