“If in your former book, ‘The Blood Covenant,’ you made [as was suggested by an eminent German theologian] the first successful attempt to write a theology of the blood, you have given us in your most recent work a thorough investigation on the significance and history of the primitive altar upon which blood was shed by men entering into a covenant with God or their fellow-men. Surely your two books ‘The Blood Covenant,’ and ‘The Threshold Covenant’ belong together, and should therefore be studied together. One supplements the other, and the former furnishes the key to a full understanding of the facts presented in the latter; and so again on the other side. “It must have cost you decenniums to gather all the material which you lay before the reader in such a systematic form. All the nations of the world, civilized and uncivilized, ancient and modern, seem to have contributed their share to your stately structure, which has my full admiration. Viewed in this light alone, your book will always prove a regular storehouse of knowledge for students of primitive rites and religions, and of various other kindred subjects. “It is, of course, impossible for any specialist in one certain line to fully estimate the hundreds of new features presented in your recent work. It would be bold on my part, at least, to express an opinion on questions with which I am not entirely familiar. As, however, you treat facts which bear closely upon my special line of investigation,–the oldest history, languages, and civilization of the Euphrates valley, and of their rites in general,–I can heartily assure you that, according to my examination, you have proved your main points beyond question. “It is first of all sure that you are the first who fully recognized, and in fact rediscovered, the world-wide importance and fundamental significance of the threshold in all ancient religions. You have re-established an ancient rite which was practically entirely forgotten by modern scholars. By restoring the threshold to its proper place in primitive religions, you have rendered a great service to comparative religion, archeology, and even philology. Many a statement by ancient writers was obscure to us, many a word puzzling as to its original etymology and significance, and not a few facts brought to light by recent excavations remained incoherent and mysterious, because we had lost sight of the significance of the threshold, which, very appropriately, you style the first altar of the human race.