From Truman G. Madsen’s book ‘Joseph Smith the Prophet’, we read:
We turn now to some of the responses of those who heard the Prophet (Joseph) as a speaker, and how they attempted to describe what they heard. Let me first say that, so far as can be determined, the Prophet never read a book on the principles of “rhetoric” or “elocution.” What he had been counseled to do as a speaker came strait through the channel of revelation. In that mode, while he was away on a mission, he received what is now section 100 of the Doctrine and Covenants. He was counseled to “declare whatsoever thing you declare in my name, in solemnity of heart, in the spirit of meekness in all things,” and that if he would do this, “the Holy Ghost shall be shed forth in bearing record unto all things whatsoever ye shall.(11) The Lord makes that a commandment. In this connection, Doctrine and Covenants 84, with parallels elsewhere, contains the statement, “Treasure up in your minds continually the words of life, and it shall be given you in the very hour that portion that shall be meted unto every man.”(12) The last half of that promise is widely quoted in the Church — in the very hour of our need the Lord will give us what we should speak. But this omits the governing condition, the prior cause: if you treasure up continually the words of life, then — and the sense of the expression is only if you do this — you will be given in the very hour what you should say.
Being immensely weighted with every variety of responsibility and concern, the Prophet was not able consistently to set aside long periods of time for study, though he always made the time for up-reaching prayer and communion. On one occasion he arose and said, “I am not like other men. My mind is continually occupied with the business of the day and I have to depend entirely upon the living God for everything I say on such occasions as these”13 (see below). Then he proceeded to give one of the greatest discourses of all time. He was, “treasuring up continually” in all that phrase implies. Therefore he was blessed with discernment to know what should be given by way of milk here and what by way of meat there.
Incidentally, the Prophet, loving, playful, and cheerful though he was did not balk when he was inspired to rebuke or admonish with sharpness. After the rebuke he would show forth an increase of love to the one rebuked, in accordance with Doctrine and Covenants 121:43. But he could be towering when he rebuked and it could penetrate to the very vitals.
Illustrative of this is a story still carried in the family lore of Brigham Young’s descendants but, so far as I know never recorded. It says that in a meeting the Prophet rebuked Brigham Young from his head to his feet for something he and done, or something he was supposed to have done but hadn’t — the detail is unclear. And it may well have been that the Prophet was deliberately putting Brigham Young to the test When he had finished the rebuke, everyone in the room waited for the response. Brigham Young rose to his feet, He was a strong man. He could have responded: ” Now, look, haven’t you read that you’re not supposed to rebuke in public, but only in private?” Or, “Brother Joseph, doesn’t it say something in the revelations about persuasion, and long suffering and gentleness and meekness?” Or, “you’re dead wrong. It’s not so.” But he said none of the above. In a voice everyone could tell was sincere, he said simply, “Joseph, what do you want me to do?” And the story says that the Prophet burst into tears, came down from the stand, threw his arms around Brigham and said, in effect, “Brother Brigham, you passed.”15 (below)
~ Truman G. Madsen (deceased) was a well known and respected LDS author, thinker and BYU faculty member. The publication from which this was taken is called ‘Joseph Smith the Prophet’, Bookcraft 1989, pages 87-88.
13. Teachings of the Prophet Joseph Smith, p.320 This statement was made at the funeral of Judge Higbee.
15. Recounted to author, Brother Madsen, by Elder Hugh B. Brown (of the Quorum of the Twelve Apostles)deceasedad, whose wife Zina, was a granddaughter of Brigham Young.

