Karl Barth is often said to be a proponent of Christian universalism. The logic is that Barth’s doctrine of election, whether he likes it or not, commits him to affirming some form of a Christian universalism (i.e., the notion that all people of all time will eventually freely submit to the reality that Jesus Christ is Lord; even if that finally only happens in hell itself). But 
Barth adamantly rejected this supposed necessity of his theological trajectory. As Douglas Campbell writes:
Barth has often been accused of universalism, but he steadfastly denied it (see the final paragraph of CD III/2), and we owe it to his intelligence and subtlety to at least examine his claims in this relation. One of his key points was a denial of any overriding of human freedom by God, although he defines that topic very carefully. This stance certainly excludes crude forms of universalism (and I myself endorse this exclusion). Another key point was his recognition of God’s freedom, which certainly seems fair as well. God acts freely, and so we cannot really circumscribe God’s activity in advance. Barth did point toward the legitimacy of hope, and even prayer, for universal salvation. However, he stopped short of predicting it. (Part of Barth’s repudiation is explicable in terms of his rejection of a form of universalism understood in a “hard” Origenist fashion, as seen also in Maximus the Confessor, which overrules divine agency. These theologians claim that salvation of all must follow on the successful theosis of all—a Pelagianizing account of universalism that Barth was quite right to reject.)
Having said this. [sic] I am not sure that his development of the notion of the ultimate victory of God at length in CD IV/3 did not lead him to a theological location where the denial of universalism would in fact lead to the denial of key christological warrants, even after taking human freedom fully into account. And his christological account of election can also be invoked here in relation to God’s freedom (II/2). God’s freedom is not freedom per se but his free love towards us, which is definitively enacted in the Son prior to the foundation of the world. So perhaps some Sachkritik in relation to Barth himself is in order at this moment.[1]
Before we engage further with the implications that Campbell draws out for us in regard to Barth’s rejection (or not) of Christian universalism, let us address a methodological matter. Maybe the reader has never heard of Sachkritik. In order to offer some insight into this (which has greater development here), I. Howard Marshall writes this on what Sachkritik entails:
I shall continue to refer to the method by this German name, but it will be helpful to note that the possible English equivalents for it include ‘content criticism’, ‘theological criticism’, ‘critical interpretation’, ‘material criticism’ and ‘critical study of the content’.7
It will not surprise you in the least that among the heroes of our tale, or, if you prefer it, the villains of the piece, we must mention R. Bultmann. Here is a comment on his Theology of the New Testament by Markus Barth, who asks how a conscientious exegete can develop a systematic exposition of Paul’s theology that contradicts part of the source material:
[He can do so] only when he feels himself called to Sachkritik on Paul, ‘just as Luther used it, for example, on the Epistle of James’. The victims of Bultmann’s Sachkritik include some Pauline statements on the Holy Spirit, the resurrection, the second Adam, original sin, knowledge. Naturally the hostile crumbs swept to one side by Sachkritik include the statements about creation, predestination and the incarnation of Jesus Christ which Bultmann has demythologized. In any case Bultmann is convinced that he is putting the ‘real intention’ of Paul over against the actual words of the text.… When Bultmann attributes the use of juridical, mythological, cosmological, mystical and idealistic concepts to a ‘superstitious understanding of God, the world and mankind’, he expresses as clearly and simply as possible the criteria for his Sachkritik.
Now we must be clear as to what is going on here. It is not quite the same as the attitude expressed in the words: ‘I want to be free to disagree with Paul.’ In that wish there is expressed a contrast between what Paul said and what I think, and if we disagree, so much the worse for Paul. That is a question of Paul’s authority over against my own authority. We’ll come back to that in a moment. Rather what has been expressed is a contrast between one part of Scripture and another which stands in contradiction to it, or between what a writer actually says and what he really means. According to Tom Wright, we find an example of this in the procedure adopted by proponents of universalism.
The proponents of universalism admit very readily that their doctrine conflicts with much biblical teaching. What they are attempting, however, is Sachkritik, the criticism (and rejection) of one part of Scripture on the basis of another.
That is to say, critics observe or search for places where there are doctrinal contradictions in Scripture and then have to decide which passage they are to follow in preference to the other.[2]
Essentially, as Marshall clarifies further, what the above reduces to is the following: “. . . The result of such analysis is inevitably to force a judgment as to which texts are to be taken as expressing the real intention of a writer or the main thrust of the scripture and how they are to be interpreted. . . .”[3]
All of the aforementioned to note that Sachkritik is a modern (German) development that took place in post-Enlightenment biblical studies. The quest, as it were, is for the exegete to properly identify what the total intention of the biblical author is in light of their whole corpus rather than simply focusing on various texts here and there. That is, there might be something in the thought of the author of Holy Scripture, that is in their respective teaching, that seems to contradict their broader teaching when their whole corpus is taken into account. It is the total teaching that then serves as determinative of how the exegete ought to understand the particular (potentially contradictory relative to the total), and place that into the total teaching of said biblical author. The criteria for this endeavor takes us too far afield to develop further for our purposes. Suffice it to say: What Campbell is referring to in Barth, and the Apostle Paul prior, is how we ought to understand these authors from within the ambit of their total teaching on a particular theological topic; in our current case that involves a doctrine of Christian universalism.
With the above noted let’s return to the question at hand: should Barth be understood to finally be teaching a doctrine of Christian universalism when his total oeuvre is considered? Campbell, seems to think that just maybe we ought to conclude that if Sachkritik is applied to the total theology of Barth, as developed his Church Dogmatics, that Barth’s theology must necessitate in the affirmation of a Christian universalism. But Campbell doesn’t finally take the step of absolutizing this for Barth, even by way of engaging in a Sachkritik.
Prior to Campbell’s thinking on Barth, he has been engaging in an exegesis on Paul’s theology with particular reference to his thinking on eschatological doctrina, such as annihilationism and Christian universalism. Campbell shows that in one sense Paul seems to teach a doctrine of annihilationism; at least as the inner-logic of his teaching is teased out. But when Paul is used to interpret Paul, as Campbell suggests ought to be an interpretive employment we ought to take seriously, as Campbell argues, what we end up with is a Paul who sounds a lot like Barth’s own ending; again, according to Campbell. For Campbell, the Apostle Paul’s total teaching ends up having a christological universalism latent to it. In other words, according to Campbell, Paul’s total theology, even when recognizing that he also has an apparent teaching of ‘annihilation’ present (when it comes to the final judgment), reduces to the notion that all of creation (cf. Rom. 8 etc.) will finally be redeemed. And yet, as with Barth, because of various other passages and teachings in Paul, Paul doesn’t end up with a decisive or absolute Christian universalism. Campbell sees this in a corollary with Barth’s own conclusions; that is, Campbell, I would suggest, sees Barth’s teaching and thinking on these things, largely reflective of the Apostle Paul’s own inner-theological teachings on a doctrine of last and final things in regard to salvation. But this is a sachkritik reading of the Apostle (if not of Barth as well). Some might sense in sachkritik an antecedent in what Luther called an analogy of faith, or what we might call an analogy of Scripture. That is, the deployment of the clearer teachings of Scripture as the means by which we interpret the less clear. I think it would be right to see this, in principle, as an antecedent to sachkritik even if sachkritik finally took shape under different (modern) pressures.
Conclusion
After all of the above is considered what do I think? I agree mostly with Campbell. I don’t think Barth ought to be understood as endorsing a dogmatic Christian universalism; at most I think we see a very hopeful and prayerful Christian universalism in Barth’s theology. I also tend to agree with Campbell on Paul’s teaching in this regard; even if we didn’t have time to directly deal with his development on that, per se. I would always fall back to the Barth of CD III (as Campbell reads him), and emphasize a doctrine of Divine freedom as determinative of all things; including the notion that it could be a possibility that it would be in keeping with God’s purview (and character) to have made a way for people, all people, post-mortem, even while in the gruel of hell, to finally, by the Spirit, bow the knee and confess Jesus as Lord. But I don’t take this dogmatically, and my hopefulness in this is only informed by the fact that God is God and I am not; as such He could surprise us this way, and not be found to have contradicted His Word to us now and then. But this is up to God, and as far as we know now, a doctrine of dogmatic Christian universalism imposes a determination upon God that God Himself has not committed Himself to, per se. If we are going to be ‘good’ sachkritiks the total canonical teaching of Holy Scripture teaches a final judgment of the (spiritually) dead that appears to be a final and unending judgment of the type that the devil and his minions will experience. Jesus taught this, and so I think it is best to temper any notion of a purported dogmatic Christian universalism by the reality that God is God, and thus the only free agent who finally determines these things. But as it stands now, based on the teaching of Scripture, unless of course we are going to step in and read Scripture from a canon within the canon, a dogmatic Christian universalism is not on the table. That is, unless the exegete has already decided a priori that the total teaching of Scripture does in fact presuppose a dogmatic Christian universalism, and then use that presupposition as regulative for how they arrive at their respective exegetical conclusions on these matters. I don’t think that is warranted; again, because of God’s freedom over against ours as His subjects.
[1] Douglas A. Campbell, Pauline Dogmatics: The Triumph of God’s Love (Grand Rapids, Michigan: William B. Eerdmans Publishing Company, 2020), 440.
[2] I. Howard Marshall, “An Evangelical Approach to Theological Criticism,” Themelios (Vol. 13:3): na.
[3] Ibid.