After Jesus ordained His apostles, He delivered a discourse known as the Sermon on the Mount.
As word spread that the Messiah had been found, people came from the densely populated towns along the coasts of the Sea of Galilee, and from the shores of Tyre and Sidon. As they sought Him out, they thronged about Him to hear His words, to be near Him and even to touch His robe. Jesus ascended a mountain near the Sea of Galilee where He taught His disciples.It is commonly believed that Jesus presented the same sermon, or versions of it, to different people in different places. This is verified by the fact that the Book of Mormon has a version of the sermon as delivered by the Savior to the Nephites on the American continent after His resurrection. (See 3 Nephi, chapters 12-14.)
It is generally understood that the initial Sermon on the Mount was delivered to the Savior's apostles and select followers, or disciples, and not to the masses.
Elder James E. Talmage wrote in Jesus the Christ: "Some portions of the sermon were expressly directed to the disciples, who had been or would be called to the apostleship and in consequence be required to renounce all their worldly interests for the labors of the ministry; other parts were and are of general application."
The most extensive account of the Savior's Sermon on the Mount is Matthew, chapters 5-7. A brief synopsis, sometimes referred to as the Sermon on the Plain, is in Luke 6:20-49.