With permission of Kirk Richards, www.jkirkrichards.com.
J. Smith, Jr., Teachings, 4 May 1842, p. 237.
B. Young, 6 April 1853 - B, p. 31; B. Young, Discourses, p. 416.
 Here is a sampling of places where this definition is cited, based on a cursory search of Church-published sources: Duties and Blessings of the Priesthood: Basic Manual for Priesthood Holders, Part B; Aaronic Priesthood Manual 3; Young Women Manual 3; Preparing to Enter the Holy Temple; Ensign, January 1972; December 1986; October 1994, February 1995, October 2007; Liahona, June 1992, October 1997, October 2007; New Era, June 1971, September 1973, June 1975.
 In Webster’s 1828 Dictionary (N. Webster, Dictionary), the definition of “key” includes the ideas of “An instrument for shutting or opening a lock,” and also “That which serves to explain anything difficult to be understood.”
“Sign” is explained in Webster as “A token; something by which another thing is shown or represented; any visible thing, any motion, appearance or event which indicates the existence or approach of something else” (cf., e.g., Hymns of the Church of Jesus Christ of Latter-day Saints, Hymns (1985), Redeemer of Israel, #6: “The tokens already appear”), and also, citing Luke 1:62 (“And they made signs to his father”), “a motion, action, nod, or gesture indicating a wish or command” (cf. J. A. Simpson et al., OED, 1764:449: “A gesture of the hand, head, etc., serving to convey an intimation or to communicate some idea”).
“Token” is defined in Webster as “A sign; something intended to represent or indicate another thing or an event,” and also “A mark. In pestilential diseases, tokens are livid spots upon the body, which indicate the approach of death” (Cf. W. Shakespeare, Love's Labor's Lost, 5:2:423, p. 206: “The Lord’s tokens on you do I see”). Also, in the Oxford English Dictionary, “a word or material object given to authenticate a person, message, or communication” and “Something given as the symbol and evidence of a right or privilege, upon the presentation of which the right or privilege may be exercised” (J. A. Simpson et al., OED, 2074:196).
“Signs” and “tokens” were also used in Freemasonry—see, e.g., Benjamin Franklin’s famous tribute to the value of its signs and tokens (cited in H. L. Haywood, Symbolical, p. 131):
These signs and tokens are of no small value; they speak a universal language, and act as a password to the attention and support of the initiated in all parts of the world. They cannot be lost so long as memory retains its power. Let the possessor of them be expatriated, shipwrecked or imprisoned; let him be stripped of everything he has in the world; still these credentials remain and are available for use as circumstances require.
For a debunking of the idea that LDS temple ordinances are a simple derivation from Freemasonry, see M. B. Brown, Exploring. Brown’s more in-depth manuscript dealing with this topic still awaits publication.
D. H. Oaks, To Become, p. 32. See also J. E. Faulconer, Self-Image.
H. W. Nibley, Meaning of Temple, p. 26.
 See Alma 42:15-26.
S. Mowinckel, Psalms, 1:181 n. 191.
J. H. Eaton, Psalms Commentary, 118:19-22, p. 405. See also Psalm 24:3-4.
H. W. Nibley, Message 2005, p. 451.
 D&C 20:77.
D&C 109:22, 26, 79. See also D. A. Bednar, Name, p. 98; D. H. Oaks, Taking Upon Us.
 D&C 130:11; cf. Revelation 2:17.
 D&C 130:10.
 D&C 130:9.
 See John 17:3.
 James Tissot (French, 1836-1902). Reconstruction of Jerusalem and the Temple of Herod Seen from the East, 1886-1894. Image: 8 7/8 x 16 3/8 in. (22.5 x 41.6 cm). Brooklyn Museum, Purchased by public subscription, 00.159.7. In J. F. Dolkart, James Tissot, p. 204. With permission.
T. G. Madsen, Putting, p. 459.
 Cf. Isaiah 29:13; Matthew 15:7-9.
 Psalm 118:20.
S. Mowinckel, Psalms, 1:180.
 Psalm 24:6. Parry sees an allusion to a prayer circle in this verse (D. W. Parry, Psalm 24).
W. J. Hamblin et al., Temple, p. 27, cf. p. 182. See also 1 Kings 8:27-30; D&C 110:7.
 “With” = “in’” in Hebrew (M. Barker, Hidden, p. 44; cf. Matthew 21:9).
The meaning of being “willing to take upon [us] the name of Jesus Christ” in the sacrament is clear in light of temple ordinances (D. A. Bednar, Name, p. 98; D. H. Oaks, Taking Upon Us; D&C 20:77; 109:22, 26, 79). Truman G. Madsen writes: “You are required as disciples of Christ to come once in seven days and covenant anew to take upon you the name of Jesus Christ. In the house of the Lord you come to take upon you His name in the fullest sense” (T. G. Madsen, Temple and Mysteries, p. 33).
 Cf., e.g., Revelation 7:3, 14:1, 22:3-4, D&C 133:18. Referring to the hundred and forty-four thousand in Revelation 14:1, Barker further explains (M. Barker, Revelation, p. 229):
… the servants of God-and-the-Lamb (a unity) worship Him in the place where the Lord God is their Light, and they have His Name on their foreheads. In other words, they have been admitted to the Holy of Holies/Day One, and they bear on their foreheads the mark of high priesthood, the Name…
The Prophet Joseph Smith similarly taught that the sealing in the forehead (J. Smith, Jr., Teachings, 13 August 1843, p. 321):
… signifies sealing the blessing upon their heads, meaning the everlasting covenant, thereby making their calling and election sure.