Baeck's “Wesen des Judentums” first appeared in 1905, in the notable series issued by the Gesellschaft zur Förderung der Wissenschaft des Judentums, a modest brochure of 167 pages. In the new edition it has grown to nearly double its original size. The conception of the task, general plan of the work, and method of treatment remain unchanged; but within this framework it is largely a new book. Especially the second part, on the Ideas of Judaism, has been completely rewritten and greatly expanded, giving evidence throughout of recurrent occupation with the subject and maturing reflection. The book is written primarily for Jewish readers, but I know of no book to which any one who seriously wants to know what Judaism is to those who know it best can more confidently be sent for an answer. The author gives neither a history nor a theology — still less an apology — but an exposition and an appreciation of the character of the religion, and of its constitutive ideas, under the heads, Faith in God, and Faith in Men (ourselves, others, mankind as a whole), concluding with a chapter on the Maintenance of Judaism. The treatment is marked by philosophic breadth and insight, combined with a fine art of presentation. One whose calling requires him to read many books, and who has suffered more than his due from authors who seem to think that their reputation or the importance of their matter licenses them to write in a prose that neither gods, men, nor publishers ought to tolerate, may be pardoned for emphasizing his appreciation of a volume which he has read not only with profit but with delight.