A witness is a statement or other evidence that something is true. It can also refer to someone who gives a statement based on personal knowledge. In The Church of Jesus Christ of Latter-day Saints, witness often refers to someone who bears witness, or testimony, of something he or she has experienced and knows to be true.
The Lord taught early Church leaders that “in the mouth of two or three witnesses shall every word be established” (Doctrine and Covenants 6:28; see also Matthew 18:16). Most of the important events in the Restoration of the Church followed the pattern of having multiple witnesses testify of their truthfulness. The Three Witnesses to the Book of Mormon testified that an angel showed them the gold plates and that the record was “translated by the gift and power of God” to become the Book of Mormon (“The Testimony of Three Witnesses,” Book of Mormon). The Eight Witnesses testified that Joseph Smith showed them the gold plates and that they were able to touch them and examine the engravings. Joseph Smith and Oliver Cowdery were present at and testified of the restoration of the priesthood and priesthood keys (see Doctrine and Covenants 13; 110; Joseph Smith—History 1:68–72).
The pattern of witnesses is followed in the Church today. When a person is baptized, two witnesses, approved by the presiding authority, observe the baptism to make sure it is performed properly. Baptized members of the Church, including children and youth, may serve as witnesses. Men, women, and youth with current temple recommends may act as witnesses for vicarious baptisms for the dead. Endowed men and women with current temple recommends may act as witnesses for temple ordinances, including temple sealings.
As they partake of the sacrament, Church members “witness unto … God” that they are willing to take upon themselves the name of Christ, always remember Him, and keep His commandments (see Doctrine and Covenants 20:77, 79).
Apostles of the Church are called to be “special witnesses of the name of Christ in all the world” (Doctrine and Covenants 107:23; see also Acts 1:21–22; 4:33). As such, they testify to all people of the reality of Jesus Christ, the truthfulness of His gospel, and the importance of His Atonement to all people. Similarly, as we gain a testimony of the gospel and share what we believe through our words and actions, we “stand as witnesses of God at all times and in all things, and in all places” (Mosiah 18:9).