'Frederick Delius’s Pianoforte Concerto in C minor is to my mind the most important, the most deeply musical and emotionally significant concerto produced for several decades. It is not merely a fine pianistic concerto, but apart from all that a glowing representative work by one of the greatest creators of all time. To many keen observers of modern compositional developments, the great Frederick Delius seems to tower above most of all his contemporaries because of the irresistible emotional power, passion, and inner sincerity of his creations. A wizard in orchestration, a harmonist second to none, it is the humans soul behind all his other marvellous qualities that marks him out as a genius among geniuses, and makes him so particularly touching and endearing, and accounts for the unique position among modern composers held by Delius in England, Germany, Holland and elsewhere, and the extraordinary international vogue of such complex creations as Brigg Fair, Paris, Dance Rhapsody, Sea-Drift, Appalachia, Mass of Life, On Hearing the First Cuckoo in Spring, etc.
His polyphony is marvellous and has an indefinable Bach-like quality that is no less noticeable in his emotional make-up and in the non-effect-seeking sincerity and depth of his whole being and utterance. His artistic soul is akin to great cosmic men such as Bach, Wagner, Goethe, Walt Whitman, Milton – he is most at home in great broad lines, and his work glows with a great lovingness, almost religious, in its all-embracing and cosmic breadth'.
From Great Pianists on Piano Playing edited by James Francis Cooke Theo Presser 1913 [with minor edits]