A compilation of 139 talks and extemporaneous discourses given by "Abdu"l-Baha on the fundamental principles of the revelation and teachings of Baha"u"llah - principles that form the basis of the the universal peace Baha"u"llah has promised shall come. Among the multitude of subjects discussed are the coming of age of the human race, the oneness and continuity of the Manifestations of God, and the oneness of religion as a social force for establishing world order and peace. These talks were given during "Abdu"l-Baha"s 1912 visit to the United States and Canada. They are a priceless resource for studying the language and the personal example of "Abdu"l-Baha.