What role do we play in sanctification? Before we can answer this question, we need to define sanctification. Sanctification is the lifelong process of being conformed to the image of Christ. Scripture speaks of sanctification as both positional and progressive. We have been sanctified in the past in the sense that all Christians at the moment of justification are called out of the unbelieving world and set apart for service to God (1 Cor 6:11). At the same time, it is a process that will never be completed until we are glorified in the presence of Christ. Christlikeness is the goal of sanctification and therefore we must never take our eyes off of Jesus who perfectly obeyed God in our place. Sanctification must be distinguished from justification, but they are never separated from one another as if one could exist in the life of a Christian without the other.
Both God and man have a role to play in the process of sanctification. Whereas regeneration is monergistic, sanctification is synergistic in the sense that we have an obligation to pursue personal holiness. But we can only make progress in holiness because it is God who works within us (Phil 2:12-13). We work only because God first works in us and his working will not be finally frustrated (Jer 32:40; Phil 1:6; 2 Cor 3:18; 1 John 5:18). The exhortations and warning passages of Scripture are the effectual means by which the Holy Spirit works to bring Christlikeness to us (2 Cor 7:1; Heb 3:14). Our good works and holiness do not save us, but are the certain evidences and results of regeneration without which no man will see the Lord (Heb 12:14). As Paul Washer explains, “Our growth in holiness is the evidence of our salvation. We are not saved because we are holy, but true salvation will always lead to true holiness because as we have already learned, God is doing a perfect work in the life of every Christian” (The One True God, 73).
We have an obligation as Christians to take heed of the many admonitions, warnings, and exhortations of Scripture because they are the very words of God and a means God has ordained to sanctify us (John 17:17). Rather than seeing these commands as a burden, we should joyfully long to serve God with all that is within us. Because God is holy, we are called to be holy as he is holy as we walk in imitation of him (Eph 5:1; 1 Pet 1:15-16). The Christian life is a pilgrim journey and constant fight against sin that never ends. We can never be sinlessly perfect in this life as Paul says, “Not that I have already obtained this or am already perfect, but I press on to make it my own, because Christ Jesus has made me his own” (Phil 3:12). We press on because we are certain of our salvation. Since Christ has made us his own, we are eternally secure in him and our security should motivate us to love him more.
A key text that helps us understand the work of sanctification is Philippians 2:12-13: “Therefore, my beloved, as you have always obeyed, so now, not only as in my presence but much more in my absence, work out your own salvation with fear and trembling, for it is God who works in you, both to will and to work for his good pleasure.” We must remember that salvation in the Bible is an umbrella term that encompasses election, effectual calling, regeneration, justification, sanctification, and glorification. The salvation Paul speaks of here is the work of sanctification rather than justification which is a past reality bringing us peace with God (Rom 5:1). But we can only work out our sanctification because God is at work within us. We do it with fear and trembling because we are in the presence of God whom we are called to fear. It is not a fear that we might lose our salvation, but the fear of standing in God’s presence as Isaiah once did (Isa 6:1-8). Sanctification will be effectual because God is at work in us and his work is perfect and cannot fail (Deut 32:4). We can err by denying that sanctification is our work to which we are called or by denying that God is ultimately behind it and causing us to walk in his laws (Jer 32:40). We must keep both God’s role and our role in sanctification in healthy tension without denying the reality of either one.