Old Testament

Deuteronomy 19:15

One witness shall not rise up against a man for any iniquity, or for any sin, in any sin that he sinneth: at the mouth of two witnesses, or at the mouth of three witnesses, shall the matter be established.

New Testament

Matthew 18:16

But if he will not hear thee, then take with thee one or two more, that in the mouth of two or three witnesses every word may be established.

2 Corinthians 13:1

This is the third time I am coming to you. In the mouth of two or three witnesses shall every word be established.

John 5:31

If I bear witness of myself, my witness is not true.

Book of Mormon

2 Nephi 11:3

And my brother, Jacob, also has seen him as I have seen him; wherefore, I will send their words forth unto my children to prove unto them that my words are true. Wherefore, by the words of three, God hath said, I will establish my word. Nevertheless, God sendeth more witnesses, and he proveth all his words.

2 Nephi 27:12-14

12 Wherefore, at that day when the book shall be delivered unto the man of whom I have spoken, the book shall be hid from the eyes of the world, that the eyes of none shall behold it save it be that three witnesses shall behold it, by the power of God, besides him to whom the book shall be delivered; and they shall testify to the truth of the book and the things therein.
13 And there is none other which shall view it, save it be a few according to the will of God, to bear testimony of his word unto the children of men; for the Lord God hath said that the words of the faithful should speak as if it were from the dead.
14 Wherefore, the Lord God will proceed to bring forth the words of the book; and in the mouth of as many witnesses as seemeth him good will he establish his word; and wo be unto him that rejecteth the word of God!

Ether 5:2-4

2 And behold, ye may be privileged that ye may show the plates unto those who shall assist to bring forth this work;
3 And unto three shall they be shown by the power of God; wherefore they shall know of a surety that these things are true.
4 And in the mouth of three witnesses shall these things be established; and the testimony of three, and this work, in the which shall be shown forth the power of God and also his word, of which the Father, and the Son, and the Holy Ghost bear record—and all this shall stand as a testimony against the world at the last day.

 

Ether 5:4

And in the mouth of three witnesses shall these things be established; and the testimony of three, and this work, in the which shall be shown forth the power of God and also his word, of which the Father, and the Son, and the Holy Ghost bear record—and all this shall stand as a testimony against the world at the last day.

Doctrine and Covenants

Doctrine and Covenants 5

1 Behold, I say unto you, that as my servant Martin Harris has desired a witness at my hand, that you, my servant Joseph Smith, Jun., have got the plates of which you have testified and borne record that you have received of me;
2 And now, behold, this shall you say unto him—he who spake unto you, said unto you: I, the Lord, am God, and have given these things unto you, my servant Joseph Smith, Jun., and have commanded you that you should stand as a witness of these things;
3 And I have caused you that you should enter into a covenant with me, that you should not show them except to those persons to whom I commanded you; and you have no power over them except I grant it unto you.
….
9 Behold, verily I say unto you, I have reserved those things which I have entrusted unto you, my servant Joseph, for a wise purpose in me, and it shall be made known unto future generations;
10 But this generation shall have my word through you;
11 And in addition to your testimony, the testimony of three of my servants, whom I shall call and ordain, unto whom I will show these things, and they shall go forth with my words that are given through you.
12 Yea, they shall know of a surety that these things are true, for from heaven will I declare it unto them.
13 I will give them power that they may behold and view these things as they are;
14 And to none else will I grant this power, to receive this same testimony among this generation, in this the beginning of the rising up and the coming forth of my church out of the wilderness—clear as the moon, and fair as the sun, and terrible as an army with banners.
15 And the testimony of three witnesses will I send forth of my word.
….
23 And now, again, I speak unto you, my servant Joseph, concerning the man that desires the witness—
24 Behold, I say unto him, he exalts himself and does not humble himself sufficiently before me; but if he will bow down before me, and humble himself in mighty prayer and faith, in the sincerity of his heart, then will I grant unto him a view of the things which he desires to see.
25 And then he shall say unto the people of this generation: Behold, I have seen the things which the Lord hath shown unto Joseph Smith, Jun., and I know of a surety that they are true, for I have seen them, for they have been shown unto me by the power of God and not of man.
26 And I the Lord command him, my servant Martin Harris, that he shall say no more unto them concerning these things, except he shall say: I have seen them, and they have been shown unto me by the power of God; and these are the words which he shall say.
27 But if he deny this he will break the covenant which he has before covenanted with me, and behold, he is condemned.
28 And now, except he humble himself and acknowledge unto me the things that he has done which are wrong, and covenant with me that he will keep my commandments, and exercise faith in me, behold, I say unto him, he shall have no such views, for I will grant unto him no views of the things of which I have spoken.
29 And if this be the case, I command you, my servant Joseph, that you shall say unto him, that he shall do no more, nor trouble me any more concerning this matter.
30 And if this be the case, behold, I say unto thee Joseph, when thou hast translated a few more pages thou shalt stop for a season, even until I command thee again; then thou mayest translate again.
31 And except thou do this, behold, thou shalt have no more gift, and I will take away the things which I have entrusted with thee.
32 And now, because I foresee the lying in wait to destroy thee, yea, I foresee that if my servant Martin Harris humbleth not himself and receive a witness from my hand, that he will fall into transgression;

Doctrine and Covenants 6:28

And now, behold, I give unto you, and also unto my servant Joseph, the keys of this gift, which shall bring to light this ministry; and in the mouth of two or three witnesses shall every word be established.

Doctrine and Covenants 17:1-6

1 Behold, I say unto you, that you must rely upon my word, which if you do with full purpose of heart, you shall have a view of the plates, and also of the breastplate, the sword of Laban, the Urim and Thummim, which were given to the brother of Jared upon the mount, when he talked with the Lord face to face, and the miraculous directors which were given to Lehi while in the wilderness, on the borders of the Red Sea.
2 And it is by your faith that you shall obtain a view of them, even by that faith which was had by the prophets of old.
3 And after that you have obtained faith, and have seen them with your eyes, you shall testify of them, by the power of God;
4 And this you shall do that my servant Joseph Smith, Jun., may not be destroyed, that I may bring about my righteous purposes unto the children of men in this work.
5 And ye shall testify that you have seen them, even as my servant Joseph Smith, Jun., has seen them; for it is by my power that he has seen them, and it is because he had faith.

Doctrine & Covenants 128:20

“And again, what do we hear? Glad tidings from Cumorah! Moroni, an angel from heaven, declaring the fulfilment of the prophets—the book to be revealed. A voice of the Lord in the wilderness of Fayette, Seneca county, declaring the three witnesses to bear record of the book! The voice of Michael on the banks of the Susquehanna, detecting the devil when he appeared as an angel of light! The voice of Peter, James, and John in the wilderness between Harmony, Susquehanna county, and Colesville, Broome county, on the Susquehanna river, declaring themselves as possessing the keys of the kingdom, and of the dispensation of the fulness of times!”

Joseph Smith Papers

History, 1838–1856, volume A-1 [23 December 1805–30 August 1834]

Not many days after the above commandment [D&C 17] was given, we four, viz Martin Harris, David Whitmer, Oliver Cowdery and myself, agreed to retire into the woods, and try to obtain by fervent and humble prayer, the fulfilment of the promises given in this revelation; that they should have a view of the pl[ates] &c[.] we accordingly made choice of a piece of woods convenient to Mr Whitmer’s [house], to which we retired, and having knelt down, we began to pray in much faith, to Almighty God to bestow upon us a realization of those promises. According to previous arrangement, I commenced by vocal prayer to our Heavenly Father and was folowed by each of the rest in succession; we did not yet however obtain any answer or manifestation of the divine favour in our behalf. We again observed the same order of prayer each calling on and praying fervently to God in rotation; but with the same result as before. Upon this our second failure, Martin Harris proposed that he would withdraw himself from us, believing as he expressed himself that his presence was the cause of our not obtaining what we wished for: He accordingly withdrew from us, and we knelt down again, and had not been [p. 24] many minutes engaged in prayer when presently we beheld a light above us in the air of exceeding brightness, and behold, an angel stood before us; in his hands he held the plates which we had been praying for these to have a view of: he turned over the leaves one by one, so that we could see them, and discern the engravings thereon distinctly: He addressed himself to David Whitmer, and said, “David, blessed is the Lord, and he that keeps all his commandments:” when immediately afterwards we heard a voice from out of the bright light above us, saying [HC 1:54] “These plates have been revealed by the power of God, and they have been translated by the power of God; the translation of them which you have seen is correct, and I command you to bear record of what you now see and hear”.— I now left David and Oliver, and went in pursuit of Martin Harris, who I found at a considerable distance fervently engaged in prayer; he soon told me however that he had not yet prevailed with the Lord, and earnestly requested me, to join him in prayer, that he also might realize the same blessings which we had just recieved: we accordingly joined in prayer, and ultimately obtained our desires, for before we had yet finished, the same vision was opened to our view; at least it was again to me, and I once more beheld, and seen, and heard the same things; whilst at the same moment, Martin Harris cried out, apparently in an ecstasy of Joy “’Tis enough, ’tis enough; mine eyes have beheld, mine eyes have beheld”, and jumping up he shouted, Hosanna, blessing God; and otherwise rejoiced exceedingly. [HC 1:55] Having thus through the mercy of God, obtained these glorious manifestations, it now remained for these three individuals to fulfil the commandment which they had received, viz: to bear record of these things; in order to accomplish which, they drew up and subscribed the following document [Testimony of the Three Witnesses].

History, 1838–1856, volume A-1 [23 December 1805–30 August 1834]

In th[e] course of the work of translation, we ascertained that three special witnesses were to be provided by the Lord, to whom he would grant, that they should see the plates from which this work (the Book of Mormon) should be translated, and that these witnesses should bear record of the same; as will be found, recorded, Book of Mormon First edition

Almost immediately after we had made this discovery, [HC 1:52] it occurred to Oliver Cowdery, David Whitmer, and the aforementioned Martin Harris (who had came to enquire after our progress in the work) that they would have me enquire of the Lord, to know if they might not obtain of him to be these three special witnesses; and finally they became so very solicitous, and teazed me so much, that at length complied, and through the Urim and Thummin, I obtained of the Lord for them the following Revelation [D&C 17].