This is a good reflection on the Barth-von Kirschbaum relationship from Carolyn Mackie (Women in Theology). She notes some of the difficult decisions made and rightly concludes that “The production of a brilliant piece of theology is never sufficient justification for harming others.” I agree. Charlotte von Kirschbaum indeed proved indispensable to Barth’s theological work and perhaps her contribution might still have been made even had the circumstances differed.
I think I would use a stronger term than ‘unfortunate’ to describe the affair. There is, of course, much that we will never know, and the story reflects the ofttimes tragic nature of human relationships. Yet we ought not to justify, least of all religiously and theologically, that which cannot and should not be justified. It is better clearly to acknowledge that Barth crossed a line that should not have been crossed.
Mackie is also correct to assert that Barth’s theological work should be assessed in the light of this knowledge to ascertain how his domestic arrangements may have influenced his theological construction. His discussion of marriage in the Command of God the Creator is a case in point (CD III/4), and warrants further examination.