All things bear record · 3 Nephi
11 witnesses of Christ here.
And now it came to pass that when Jesus had told these things he expounded them unto the multitude; and he did expound all things unto them, both great and small. 3 Nephi 26:1–2
Jesus explains the scriptures, great and small, and says He gives them because the Father commanded it. The Son always does the will of His Father.
How we know: the verse itself names Him · the chapter heading names Him
And he did expound all things, even from the beginning until the time that he should come in his glory—yea, even all things which should come upon the face of the earth, even until the elements should melt with fervent heat, and the earth should be wrapt together as a scroll, and the heavens and the earth should pass away; 3 Nephi 26:3
Jesus taught the whole history of the earth up to the time He will come in His glory. His Second Coming and the renewal of the earth are part of His plan from the beginning.
How we know: the chapter heading names Him · a footnote points to Him · a Church study aid lists it
And even unto the great and last day, when all people, and all kindreds, and all nations and tongues shall stand before God, to be judged of their works, whether they be good or whether they be evil— 3 Nephi 26:4–5
Everyone will be resurrected and stand before God to be judged by their works. This judgment happens according to the mercy, justice, and holiness that are in Christ.
How we know: the chapter heading names Him · a Church study aid lists it
Christ — the Anointed One
If they be good, to the resurrection of everlasting life; and if they be evil, to the resurrection of damnation; being on a parallel, the one on the one hand and the other on the other hand, according to the mercy, and the justice, and the holiness which is in Christ, who was before the world began. 3 Nephi 26:5
Mormon testifies that Christ existed before the world began, and that mercy, justice, and holiness all dwell in Him. He is the eternal Son, not only a man who lived in Jerusalem.
How we know: the verse itself names Him · the chapter heading names Him · a Church study aid lists it
And now there cannot be written in this book even a hundredth part of the things which Jesus did truly teach unto the people; 3 Nephi 26:6–8
Mormon says he could not record even one percent of what Jesus taught the Nephites. What we have is a small, chosen part meant to bring later generations to Him.
How we know: the verse itself names Him · the chapter heading names Him
Behold, I was about to write them, all which were engraven upon the plates of Nephi, but the Lord forbade it, saying: I will try the faith of my people. 3 Nephi 26:11–12
The Lord personally stops Mormon from writing more so He can test His people's faith. In the context of this record of Jesus' ministry, 'the Lord' who commands Mormon is most likely Christ.
How we know: the chapter heading names Him
Therefore, I would that ye should behold that the Lord truly did teach the people, for the space of three days; and after that he did show himself unto them oft, and did break bread oft, and bless it, and give it unto them. 3 Nephi 26:13
The resurrected Lord taught for three days and then kept appearing, often breaking and blessing bread for them. The sacrament He gave them keeps His body and Atonement in remembrance.
How we know: the chapter heading names Him · a footnote points to Him · a Church study aid lists it
And it came to pass that he did teach and minister unto the children of the multitude of whom hath been spoken, and he did loose their tongues, and they did speak unto their fathers great and marvelous things, even greater than he had revealed unto the people; and he loosed their tongues that they could utter. 3 Nephi 26:14–16
Jesus ministered to the children and loosed their tongues so that even babies taught marvelous things. He values children and can reveal His greatest truths through them.
How we know: the chapter heading names Him
And it came to pass that after he had ascended into heaven—the second time that he showed himself unto them, and had gone unto the Father, after having healed all their sick, and their lame, and opened the eyes of their blind and unstopped the ears of the deaf, and even had done all manner of cures among them, and raised a man from the dead, and had shown forth his power unto them, and had ascended unto the Father— 3 Nephi 26:15
Mormon lists Jesus' miracles — healing the sick, lame, blind and deaf and raising the dead — and His ascent to the Father. These are the signs that He is the Messiah.
How we know: the chapter heading names Him
And it came to pass that the disciples whom Jesus had chosen began from that time forth to baptize and to teach as many as did come unto them; and as many as were baptized in the name of Jesus were filled with the Holy Ghost. 3 Nephi 26:17
Jesus' chosen disciples baptized in His name, and those baptized received the Holy Ghost. Baptism in His name is how people covenant to follow Christ.
How we know: the verse itself names Him · the chapter heading names Him
And it came to pass that they did do all things even as Jesus had commanded them. 3 Nephi 26:20–21
The people obeyed everything Jesus commanded, and those baptized in His name were called the church of Christ. His Church bears His name.
How we know: the verse itself names Him · the chapter heading names Him