"[...] This book delivers magnificently on its promise, and is thus of fundamental significance for anyone interested in any of these subjects, as well as being an exemplary edition of a hitherto insufficiently well-known Latin text... . In other words: this is a masterpiece of hard work, the product, clearly, of many years of industry, and a mine of information. Was it all worthwhile? The short answer is: a most vehement yes. As a text and a work of reference alone, these volumes will be indispensable; and the wealth of information contained in the historical studies will be equally indispensable, if less conclusive... These volumes deliver everything that the very best German Habilitationsschrift ought to. They are thorough and comprehensive; they are meticulous with regard to every detail; they are the product of a great deal of philological skill and literary expertise and insight; and, in addition, they are not just excellent works of medieval Latin philology (to which field the author's home department and the book series in which they are published belong), but also highly informative (albeit, and probably inevitably, to a certain extent inconclusive) studies of religious, cultural, and liturgical history to which a massive amount of erudition has been brought to bear, and without which anyone with the remotest interest in the many subjects covered within these volumes will not be able to do serious scholarship... - Shami Ghosh, Pontifical Institute of Mediaeval Studies, in: TMR 16.03.13
"[...] these magnificent volumes represent a great scholarly achievement and will be reckoned as a major contribution to understanding the hagiography of Olav Haraldsson from practically all angels and in all its aspects. [...] this investigation is extraordinary in depth and thoroughness. [...] Each of the topics dealt with will definitely be rewarding for future students. Above all LJ has given us an edition of the whole dossier of texts, soberly assessed, organized, and edited.[...] Needless to say, then, the two volumes deserve a prominent place in every institutional library caring for medieval studies." - Egil Kraggerud, in: Collegium Medievale, 29 (2016), pp. 150-163