When the Savior visited the New World, he
called twelve disciples. Them he taught with, and separately from, the multitude that had gathered to hear His words.
In the morning of the day following the Savior's first day of ministry spent among the Nephites, these twelve provide an example to all who have been called to be teachers. Elder Jeffrey R. Holland writes:
It is interesting that the twelve disciples did not have to be commanded to teach but accepted that responsibility instinctively because of their commission to be witnesses of Christ at all times and in all places. What they taught, not surprisingly, were the same lessons they had been taught the day before, "nothing varying from the words which Jesus had spoken." In the spirit of the counsel the Savior had left the night before, the twelve disciples commanded the multitude to kneel and pray to the Father in the name of Jesus, "and they did pray for that which they most desired; and they desired that the Holy Ghost should be given unto them."
(Christ and The New Covenant, Salt Lake City, UT: Deseret Book, 1997, 277-78.)
One of the things Gospel teachers need to remember is that they are to teach the words of Christ - as He taught them, and as his prophets have taught them and recorded them in scripture. Gospel instruction of any kind--seminary, Sunday school, primary, Priesthood or Relief Society, etc.--should follow this same pattern. Teach the doctrines as they are found in the scriptures, the basis for each course of study, and ponder how to use the doctrines and principles that are mentioned in the lesson manuals to bless and edify the class. As an instructor of mine reminded us during CES training, "Stick to the [gospel] trunk; avoid the branches."
Another thing that should be noted is that these disciples realized how important the Holy Ghost was for them as well as their students. They desired, and prayed for, the presence of the Holy Ghost so that the gospel truths could be taught with authority and could be
carried unto the hearts of those who heard them.
Lastly, I'll suggest the Elder Holland's mention of the "why" these disciples chose to teach the words of Christ to the multitude don't apply only to those called and commissioned as disciples or apostles - but to all of us who have entered into a covenant with the Lord through baptism. Remember the words of Alma at the Waters of Mormon to those who were desirous to come into the fold of God, explaining the covenant into which they would enter through the ordinance of baptism:
...and to stand as witnesses of God at all times and in all things, and in all places that ye may be in, even until death, ...
As disciples of Christ and members of His Church, we have covenanted to be His witness. One way we can do this is by being a witness to others of who He is by emulating His gospel teaching and sharing with others what he taught.