What are we to understand by the book which John saw, which was sealed on the back with seven seals?The time covered by the seven seals refers to things of God's "economy" during this period of "continuance." He finds "economy" is not used elsewhere in the scriptures, but does have a theological definition in the dictionary (Practical Standard Dictionary, p. 369):
A. We are to understand that it contains the revealed will, mysteries, and the works of God; the hidden things of his economy concerning this earth during the seven thousand years of its continuance, or its temporal existence.
6. Theol. A method of divine management of human affairs, or a system of laws and regulations, rites, and ceremonies; the holy scheme of creation and redemption; specif., and particular method of divine government, as the Mosaic economy.Talmage then suggests that "economy" may refer to God's dealings with men on earth rather than with the earth itself, and the hidden things in this regard refer to things that have been revealed or yet to be revealed (it would seem that "mysteries" would fit well here).
He then considers the word "continuance" and notes that its usage in the scriptures (Ps. 139:16, Is. 64:5, and Rom. 2:7) does not indicate totality of duration, but progress in advance of an earlier stage. The first volume of a magazine is not a continuance, for example, but later volumes can be. His examination of the dictionary leads to the conclusion that "continuance" refers to the current time period with an unspecified time period preceding it.
The final term he considers is "temporal." The dictionary allows "temporal" to have the same connotation as "temporary" or "current," but he finds no evidence that it should be synonymous with "physical" or "material." He finds its most usual or appropriate meaning to be "pertaining to affairs of the present life."
The three terms that Talmage analyzes harmonize with each other and all point to the conclusions that D&C 77 refers to God's dealing with man under the present time period (the collection of dispensations of the past several thousand years), and does not say anything about the time of the Creation or age of the earth, or even the antiquity of other humans or humanoids.