receiving a fulness of joy
I had a question on this part of the 2009 Gospel Principles.
"If we passed our tests, we would receive the fulness of joy that our Heavenly Father has received.
(See D&C 93:30–34.)" The 1997 GP has "our heavenly parents" instead of "our Heavenly Father".
"We learned that if we placed our faith in Him, obeying His word and following His example, we would
be exalted and become like our Heavenly Father. We would receive a fulness of joy." The 1997 GP has
"our heavenly parent
The chapter you're quoting from is about the premortal life. The earliest point that we have consistent and clear teaching on are this period of the Heavenly Council (see here), which includes the introduction of the plan of salvation, the fall of Satan, and the creation. Margaret Barker refers to this as the First Day teachings. Note that none of these teachings take place before the Father is God (in everything that means).
As for God the Father's origins, we have a handful of sources, bu
