I have been asked the question many times in one form or another: “is there a Protestant consensus on justification?” By that, the individual usually intends to discover whether there is a difference between the Lutheran and Reformed traditions on the doctrine of justification proper. Certainly, it is generally recognized that Luther put this doctrine in a more central position than it has within other forms of Protestantism. Yet, regarding the particulars of that doctrine, many argue that there is an inherent unity in both its Lutheran and Calvinistic formulation. This is an attempt at answering that question.
The areas of agreement between the Protestant traditions are not to be lightly dismissed, as several of the central components of Luther’s teaching on justification remained a strong basis for Calvin’s own formulation of the doctrine, which then was developed in the subsequent Reformed tradition. At the heart of their disagreements with Rome, Protestants shared a unifying conception of justification on two major points. First, justification is forensic in nature, rather than ontological. While inherent righteousness is an essential component of the Christian life, this does not constitute justification coram Deo. Instead, one is declared righteous on the basis of the imputed righteousness of Christ. Second, the means by which one receives this declaration is faith alone, apart from any human work.
In the confessional statements of the Lutheran and Reformed churches (both Dutch and English) these concepts are strongly emphasized. They serve as the heartbeat of the doctrine of justification, and salvation more broadly, within the entire magisterial Reformation. However, despite such commonalities, as the Lutheran and Reformed systems developed, several differences within their respective doctrines emerged.
While the notion of a central dogma by which every other doctrine if derived, supposedly being predestination for the Reformed and justification for the Lutheran, has been thoroughly debunked, the doctrine of justification does certainly play a more fundamental role in Lutheran thought than Reformed. This does not mean (as is sometimes alleged) that the Lutheran tradition ignores the other realities at work in salvation such as the inherent righteousness of sanctification. How it does play out, however, is in the precise position of justification temporally in the ordo salutis.
The Reformed and Lutheran traditions both place (subjective) justification after regeneration and faith in the logical order of the events involved in the application of redemption. However, the Reformed tradition generally speaks about justification in the past tense, as an act which occurs at the moment of conversion never to be repeated, and impossible to be lost. In the Lutheran, however, justification is a declaration which frames the entire span of the Christian life coram Deo. It is true that one can speak in the past tense of having been justified (Rom. 5:1), but that forensic act is not limited to one punctiliar event. Instead, the verdict of one’s justification is repeatedly declared and given. Revere Franklin Weidner notes the following regarding aspects of justification:
(1) It is instantaneous; not gradual or successive, like illumination or sanctification.
(2) It is perfect. Our sins are completely forgiven; not almost, or only half, or only a certain number. They are either forgiven or unforgiven. I. John 1: 7; Rom. 8:1; John 5:24.
(3) Assurance. Rom. 8:38, 39; Eph. 3: 12; Heb. 10:11
(4) Is renewed daily; for we must daily repent of our sins, and be daily, continually justified.
(5) The state of justification may be lost. John 15: 2; Heb. 6:5, 6; I. Tim. 4:1.
(6) But it may be recovered. John 6: 37; Isa. 1:18; Luke 15:11-32. 
As far as I am aware, the Reformed tradition does not have a precedent for speaking about being “daily, continually justified,” though perhaps such a notion appears somewhere that I have not encountered. The possibility of genuine apostasy in the Lutheran tradition also results in the possibility of losing this divine verdict as well, which is an impossibility in the Calvinistic system.
The other text cited by Paul in defense of justification by faith apart from works is from Psalm 32:1-2, wherein David speaks of the non-imputation of sin to those who believe. The Psalm is one of repentance, as David recalls a time of sin and confession, in which his confession results in forgiveness (Ps. 32:5) which Paul identifies as justification. David is not describing some kind of conversion experience here, as his faith began while the king was still an infant (Ps. 22:9-10). Instead, justification is counted at all times of confession and repentance. This is not to say that justification is continually lost and regained. It is better to think of justification, not just as a single act, but as a state that one is in, whose reality is continually declared and re-enacted through Word and Sacrament.
While such a discussion might seem like a mere debate of wording, I think there are significant implications of this distinction in these respective systems. There has recently been quite a bit of controversy in the Reformed world over John Piper’s differentiation between justification and final salvation. Mark Jones has demonstrated that the Reformed tradition has historically spoken about the necessity of works for salvation, as the category of “salvation,” is much broader than justification. Works are a kind of means or even cause of entrance into glory, though it is to be acknowledged that there is quite a bit of nuance as to how those terms are used. While I have continually voiced disagreement with Jones on this point, I do think that he is properly representing the Reformed tradition.
For the Lutheran tradition, works have always been removed from the category of salvation as language of good works being “necessary for salvation,” was rejected in the Formula of Concord. This is due, I think, to the conviction that justification covers the entire span of salvation for the Christian coram Deo. It is not a mere past event which then leads to other realities, but it is the continual reality of one’s relatedness to God. With this being the case, there can be no division between justification and final salvation whatsoever. This is not to say that one can only speak of salvation forensically (historically, there is a Lutheran ordo salutis which is much broader than a mere forensic justification) . However, one cannot speak of salvation without justification at the center.
Is there a Protestant consensus on justification? Yes and no. There is a consensus on forensic imputation and sola fide, but when the particularities of justification are examined, it is clear that these two traditions differ on important points.
In the Formula of Concord, justification and adoption are used synonymously. The act is not purely juridical, but also familial.