Westminster Larger catechism Q. 77.
Q. Wherein do justification and sanctification differ?
A. Although sanctification be inseparably joined with justification, yet they differ, in that God in justification imputes the righteousness of Christ; in sanctification of his Spirit infuses grace, and enables to the exercise thereof; in the former, sin is pardoned; in the other, it is subdued: the one doth equally free all believers from the revenging wrath of God, and that perfectly in this life, that they never fall into condemnation the other is neither equal in all, nor in this life perfect in any, but growing up to perfection.
Westminster Confession of Faith, Chapter 13, Section I.
They, who are once effectually called, and regenerated, having a new heart, and a new spirit created in them, are further sanctified, really and personally, through the virtue of Christ’s death and resurrection, by His Word and Spirit dwelling in them: the dominion of the whole body of sin is destroyed, and the several lusts thereof are more and more weakened and mortified and they more and more quickened and strengthened in all saving graces, to the practice of true holiness, without which no man shall see the Lord.
We see here the continuity and organic nature of these doctrines. Here are mentioned all the proceeding aspects of the Ordo Salutis; Effectual calling, regeneration, reception of a new heart and new spirit. They are not rigid. They are not spokes on a wheel. They are the roots, sinews, leaves, buds and branches of a glorious tree. They together make one thing.
So it is important for the purpose of distinction to talk about these doctrines individually, but it is crucial to acknowledge and comprehend their unity.
Now what we are talking about is the Christian being further sanctified; a new phase in the war against sin. The coup as taken place and is permanent, now the graces of God must go member to member driving lusts, worldliness and sin out.
Hebrews 10:9-10 “Behold, I have come to do your will.” He does away with the first in order to establish the second. And by that will we have been sanctified through the offering of the body of Jesus Christ once for all.
Here the word is used as a once for all action. The Confession hints and mentions this aspect of Sanctification but deals largely with that aspect that is a continual process, unequal in believers yet the continual process that brings all the elect unto life into a conformed image of Jesus Christ.
The fountain head is Christ through is Word and Spirit. The word and spirit are the means by which both the permanent and continual aspects of sanctification are accomplished. The word prayed, preached and sung by the power of the spirit accomplishes a continual washing and every time you get a little cleaner.
This does not occur in private, but in the community of God’s people. It happens in union with Christ.
There are two ways the Christian is sanctified. The Permanent aspect: the dominion of the whole body of sin is destroyed. This is an irreversible change.
Romans 6:6 We know that our old self was crucified with him in order that the body of sin might be brought to nothing, so that we would no longer be enslaved to sin.
Romans 6:14 For sin will have no dominion over you, since you are not under law but under grace.
In the Continual aspect “lusts are weakened and mortified” while the individual is being “quickened and strengthened in all saving graces.”
This is continuous and lifelong. Never coming to completion in this lifetime, and unequally present in the lives of Christians. The lusts of sin are “more and more” weakened, and believers are accordingly “more and more” quickened and strengthened in all saving graces.
This whole process is rooted in the eternal decree of God as the process by which the elect unto life are separated and purified in order to live eternally with the Godhead.
It consists in the renewal of the whole person according to the image of God.
As Larger catechism question 75 states so beautifully: renewed in their whole man after the image of God; having the seeds of repentance unto life, and all other saving graces, put into their hearts, and those graces so stirred up, increased, and strengthened, as that they more and more die unto sin, and rise unto newness of life.
The stirred up, increased and strengthened is what this chapter deals with.