Before any disagreement can be useful, the figure under discussion has to be described accurately. These two chapters take up Harnack’s portrait of Marcion as he actually drew it: a reader of Paul rather than a speculative system-builder, and a man whose supposed home in Gnosticism dissolves the moment the category is examined.
Both chapters stay close to Harnack’s own pages. The argument here is not yet about whether he was right; it is about what he saw.