In the Sanctification stage (Reformed perspective) are believers truly becoming more like Christ ("infusion" not imputed)?

Question

Believers who have been born again (regenerated) should have the desire to be conformed to Christ completely and should mourn when we find out that there are sins STILL to repent during the walk in the Spirit, which indicates that God (Holy Spirit) has not yet finished His work in us. In the Reformed tradition, this is the stage of sanctification within the whole plan of salvation, i.e. ordo salutis, so roughly:

regeneration + justification (past) -> sanctification (present) -> glorification (future)

(see a sample rough description here).

Much ink has been spilled, words said, and even fights conducted over the imputed vs. imparted vs. infused righteousness in connection with the justification stage in the Catholic vs. Protestant debate, described roughly here, and after 500 years it's very clear where each side stands and at the end of the day, it's mainly over using different terminologies to talk about roughly the same thing. This question is NOT about justification, and NOT about righteousness at all, but about our progressive conformity with the image of Christ.

In Catholicism, the map of this sanctification journey is very explicitly laid out, relatively stable, rich, and fine-grained through the teaching of venial vs. mortal sins, virtues, sacrament of reconciliation, merit, stages of holiness and examples from the saints, how God's grace interact with our will, purgative vs. illuminative vs. unitive ways, state of grace vs. state of mortal sin, what happens when we die before the sanctification work is finished (purgatory), etc. In other words, believers have a lot of concepts and tools at their disposal to track their progress, although the more saintly one becomes the larger the remaining distance one will feel to finish it, similar to how the more we know the more we feel we don't know.

But in the Reformed tradition, it seems that believers do not have as many tools nor even a reliable standard to "track our progress" as we are being transformed into the image of Christ during the sanctification stage. What should we use as a measure? Is it our sorrow over sin or our likelihood to sin? Is it tangible growth in the fruit of the spirit? Is there such a thing as sanctity? Does sanctity become the "real" property of the believer (even though it's in cooperation with the work of the Holy Spirit producing fruits in us)? Is it synergistic or monergistic? Does it even make sense to talk about "progress" similar to how in the Catholic scheme believers are becoming progressively holy? What is holiness vs. righteousness, same or different within the human person? How is it related to measurable character / virtue improvement? I hesitate to use the term "infused", but yet considering how it is the Holy Spirit at work, can we say that during sanctification we receive the infusion of grace that truly makes us more holy?

Another way to pose the question is in terms of the gap between unfinished sanctification and the beginning of glorification when we die. How would it feel, the jump between our 10%, 20%, 50%, or 90% sanctified state to 100%? Is it like everyone now has the same brand new car whether the old car has many accidents / 30 year old vs. cosmetic blemishes? In contrast, in the Catholic scheme, the feeling would be more of continuity.

A third way of asking the question is this: can a Reformed believer uses the concepts / map and the tools / practices of the Catholics? There is only one image of Christ for both traditions, one Holy Spirit that gives us grace, and one believer who is being sanctified. So why not use the same concepts/tools such as the theory of virtues, spiritual exercises, discernment of sins, etc? I realize that it can horrify Catholics to see Reformed believers trying to make progress without Catholic sacraments, or conversely it can horrify a Calvinist in another way.

I have tried to make the question acceptable to the site, so with the above background, here's the only question to answer: In the Sanctification stage (Reformed perspective) are believers truly becoming more like Christ ("infusion" not imputed)? An answer should include a reference to a scholarly article / book describing the believer's subjective perspective in the Reformed scheme of sanctification (not just doctrines from God's point of view). Comparison with the Catholic scheme of "tracking progress" is a plus.

Preliminary research:

1. 2018 blog article by Justin Dillehay, Baptist pastor with MDiv from Southern Baptist Theological Seminary, to set the stage and highlight the pastoral importance of this question: Two Pastoral Thoughts on Justification and Sanctification, includes a list of new books on Sanctification, Transformation, and Union with Christ.

2. Very promising 2017 book Sanctification by Dr. Michael Allen that can answer this question from Reformed tradition, from a new series New Studies in Dogmatics following the tradition of the venerable Studies in Dogmatics, reviewed in depth in 11(!) blog articles, and by a professor of Systematic Theology here. Quote from the latter review:

   ... the author roots the holiness of believers in the character of the God who saves them in Christ. In a time when many Christians associate the gospel more with benefits than with the Christ who brings benefits with him, this emphasis is needed desperately. The character of the holy triune God and the nature of union with Christ are some of the primary reasons why the gospel must ultimately include sanctification. It is only this line of thinking that removes the question as to why we should obey God if we are justified by faith alone in Christ alone. A man-centered gospel might be content with forgiveness without likeness to God. However, a God-centered gospel begins with forgiveness without being satisfied with anything less than perfection in holiness before the Lord in glory.

   ...

   I have one minor quibble with this book in relation to the author’s appeal to John Owen on the habits of grace. While Allen rightly points to Owen’s insistence that the Spirit infuses habits of grace in believers through their union with Christ (250–51), he neglects Owen’s equal insistence that infused habits of grace are insufficient to produce actual holiness. Owen insisted that believers need continual acts of the Spirit in every act of obedience to God. This strengthens the relationship between sovereign grace and the human responsibility to pursue holiness. Later Allen adds that infused habits of grace do not detract from “ongoing acts” of grace (254), yet this still falls short of Owen’s robust emphasis on the continual and personal acts of the Spirit in the lives of believers. This minor adjustment would make a great book even better.

3. Brief, informal survey from different Reformed theologians (Calvin, Turretin, Brakel, Hodge, Bavinck, Berkhof): Is Sanctification Monergistic or Synergistic? A Reformed Survey

4. An essay summarizing 5 Protestant tradition on Sanctification based on a 1987 book by 5 different authors Five Views on Sanctification, along with the author's reaction on each concluded by his own view. The 5 views are:

   • Wesleyan (Melvin Dieter)
   • Reformed (Anthony Hoekema)
   • Pentecostal (Stanley Horton)
   • Keswick (Robertson McQuilkin)
   • Augustinian-Dispensational (John Walvoord)

5. John Owen's Pneumatologia (1677–78) with relevant excerpts here: The Work of the Spirit in Renewing the Spiritual Life of Believers on holiness, supernatural habit, union with Christ, duties of the believer, etc.

Answer 1

I will be using Dr. William Downing's A Baptist Catechism as my source. He is a Reformed Baptist, though his position here is similar to most Reformed Presbyterians I have read on the matter.

I will begin by answering the question: No, there is no proper infusion of Christ's righteousness associated with the progressive nature of Sanctification.

First, I would not that there is a substantial distinction between the righteousness of God (which Christ possesses) and the righteousness that may be had by man, even in his complete sanctification. Downing, in his commentary on Q. 28 of the catechism describes God as "absolutely righteous". While Downing does not address Divine Simplicity in this catechism, it is ubiquitously affirmed throughout the Reformed divines of history. Thus, by divine simplicity, that is, God IS righteousness, there is no meaningful way in which a man may also possess or be infused with that righteousness, imputation remains as the only meaningful possibility.

But what of the progressive nature of this sanctification?

Q. 96: What are the two aspects of progressive or practical sanctification?

Ans: The two aspects of progressive or practical sanctification are the positive, or vivification, and the negative, or mortification of sin.

In his commentary on this question Downing answers many of the questions you offered in the OP. I'll leave the relevant sanction for you here:

Vivification. There are five elements which must be seriously considered in such sanctification or vivification: first, sin has been dethroned in every individual who has been effectually called, regenerated and converted, and thus, in everyone without exception who has been and is being sanctified. Believers are no longer under the dominating power of sin, but do commit acts of sin which must be dealt with (Rom. 6:11–14; 1 Jn. 2:1; 3:9). See Questions 114–115. The realities of union with Christ, effectual calling, regeneration and definitive sanctification must find appropriate expression in practical or progressive sanctification (Rom. 6:14; 2 Cor. 5:14–17; 1 Jn. 3:9; 1 Jn. 5:4, 18).

Second, professing believers are either subjects of the redemptive, transforming grace of God or they are graceless. There is no middle ground or place for a true Christian to continue to live in sin (Matt. 7:21–23; Acts 8:18– 24; 2 Cor. 13:5; 2 Tim. 4:10; Heb. 3:12–13; 12:7–8, 14–15).

Third, the agent or operating power in such sanctification is the Holy Spirit. Believers do not sanctify themselves in their own strength, although they are necessarily exhorted to godly living (2 Cor. 7:1; 1 Thess. 4:7; 1 Pet. 2:9). There is a gracious, operative dynamic which works to conform believers to the image of God’s Son in principle in the context of the eternal redemptive purpose (Rom. 6:14; 2 Cor. 3:17–18; Phil. 2:12–13).

Fourth, the goal of progressive sanctification is conformity to the moral character of God; specifically, conformity to the image of God’s Son (Rom. 8:29; 2 Cor. 3:17–18; 1 Pet. 1:15–16; 1 Jn. 3:1–4).

Fifth, there is an undeniable principle of progression in practical sanctification which the Scriptures clearly reveal. This progressive nature is due to the effectual work of the Holy Spirit. Thus, practical sanctification is most thoroughly described as progressive sanctification (Matt. 5:48; Rom. 12:2; 2 Cor. 7:1; Eph. 1:17–20; 3:14–19; 4:12–16; Phil. 1:9–11; 2:12–13; Col. 1:9–12; 2:6–7; 1 Pet. 1:15–16; 2:2; 2 Pet. 3:18; 1 Jn. 3:3).

Vivification may at times be feeble, static, and at times seem to even be in reverse, yet in the state of grace, such is an on–going reality. Sanctification can be illustrated by the southward flow of the Mississippi River. This river at times flows west, east and even north as it winds its way, but its tendency is south, and it ultimately flows south into the Gulf of Mexico. Divine correction is present in the form of conviction of sin and Divine chastisement (Heb. 12:4–13).

So in our sanctification, it is not an infusion of the righteousness of Christ, but rather a conformity to the image of that righteousness. The image of that righteousness that we have is the life of Christ in the Incarnation.

As for your concern about some sort of reliable measuring stick, we may find it in the churches exercise of Church Discipline.

From Downings commentary on Q. 163:

The word “discipline” is derived from the Latin, disco, “I learn”—hence the terms “disciple” or “learner,” and “discipline” or “teaching, training, submission.” The New Testament views the church as a disciplined body. The various members are to grow toward spiritual maturity individually and collectively. There is to be an increasing principle of unity pervading the congregation that is the result of such formative discipline. (1 Cor. 12:1–28; Eph. 2:21–22; 4:1–3, 11–16; 5:1–2, 21; 6:10–18; Phil. 1:9–11, 27; 2:1–5, 12– 16; 4:1–9; Col. 1:28–29; 2:6–7; 3:1–8; 2 Pet. 1:4–8; 3:18). This formative element is to manifest itself in what might be termed the “Christian Ethic” or “corporate sanctification” governing the relationship of believers to each other and to all within the assembly. (See Eph. 5:1–17; 6:5–9; Col. 3:22–25; Rom. 12, 17–21). See Question 94. Such formative discipline presupposes a church in which the Holy Spirit is actively at work in and through the proper ministry of the Word, and a church in which there is likewise the practice of corrective discipline.

We see similar language used in talking about church discipline as we do in talking about sanctification. Church discipline is one of the primary means for the mortification of sin.

If you have comments and questions, leave them and I will seek to continue improving my answer.

Edit: Responding to OP's question from Comments.

@GratefulDisciple writes:

1) clarification on righteousness vs. holiness in the sanctification stage: it seems righteousness is only imputed, which is clear for the justification stage, but in the Holy Spirit work of conforming us to Christ image, isn't believer being transformed in holiness, so the question is whether this holiness if infused/imputed?

When we speak of Sanctification in progressive terms, we must make an identification between righteousness and holiness. Properly, "Holiness" is only a declaration that something has been "set apart". So when we talk about progressive holiness, it makes little sense to speak of progressive degrees of set-apart-ness. Rather it is progressive conformity to the image of perfect holiness, which is the righteousness of the most holy one, Christ.

2) about increasing "conformity to the image of Christ". What is it in us that is increasing? Is it something we can detect subjectively, like how in Wesleyan / Catholic traditions, it's the increase in virtues (as habits), or increase in character stability? If it is detectable and increasing/decreasing in us, isn't it infusion in reality?

We may with fallible estimation evaluate our progress in holiness, indeed, as Paul writes in 2 Corinthians 13:5, "Test yourselves to see if you are in the faith; examine yourselves!" and in Galatians 6:4, "But let each one test his own work". Holiness isn't really a thing that can be infused, it is just a declaration. Progressive holiness is just being continually and further conformed to Christ's righteousness, and we may evaluate this through comparison to what Scripture teaches. But we must recognize that our evaluation is not infallible, and that our progress is not permanent, we may go through seasons where we are less or even not at all conformed to Christ's righteousness before God calls us back onto the path toward conformity. I hope this answers your questions.