How does the Savior reveal His will and doctrine to prophets, seers, and revelators? He may act by messenger or in His own person. He may speak by His own voice or by the voice of the Holy Spirit—a communication of Spirit to spirit that may be expressed in words or in feelings that convey understanding beyond words (see 1 Nephi 17:45; D&C 9:8). He may direct Himself to His servants individually or acting in council (see 3 Nephi 27:1–8).
I cite two illustrations from the New Testament.
........[The two examples are then given]
After Paul, Barnabas, and perhaps others spoke in support of Peter’s declaration, James moved that the decision be implemented by letter to the Church, and the council was united “with one accord” (Acts 15:25; see also verses 12–23).
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These same patterns are followed today in the restored Church of Jesus Christ.
http://www.LDS.org/general-conference/2012/04/the-doctrine-of-christ?lang=eng
Isn't a letter some form of publication?
Q.E.D.
