The doctrinal development of the Church for the period covered by this volume covers a wide range of subjects; the Prophet's definition of the "Kingdom of God," meaning in its narrowest as in its broadest sense, the "government of God," whether represented by a single individual, {XXIX} an institution or a great and complex organization (p. 256); the keys by which angelic administrations may be known (p. 267); the virtue of Blood Atonement (p. 296); the physical nature of God, the Father, the Son, and the Holy Spirit (p. 323, 325, 426); the earth becoming a Urim and Thummim to those who shall inherit it in its glorified and perfected state; the coming of the Son of Man; the persistence of acquired knowledge; the impossibility of being saved in ignorance (pp. 323-5). But the climax in doctrine as in moral daring is reached in this volume by the Prophet committing to writing the revelation on the eternity of the marriage covenant, and, under special circumstances and divine sanction the rightfulness, of a plurality of wives. As the time at which this revelation was given has been questioned, and also the authorship of it, extended consideration is given to both these matters in the following treatise: _The Time When the Revelation on the Eternity of the Marriage Covenant, Including a Plurality of Wives, Was Given, and its Authorship_. I. _The Date of the Revelation_. The date in the heading of the Revelation on the Eternity of the Marriage Covenant, Including the Plurality of Wives, notes the time at which the revelation was committed to writing, not the time at which the principles set forth in the revelation were first made known to the Prophet. This is evident from the written revelation itself which discloses the fact that Joseph Smith was already in the relationship of plural marriage, as the following passage witnesses: "And let mine handmaid, Emma Smith, receive all those that have been given unto my servant Joseph, and who are virtuous and pure before me."