"Mormon Underwear" is a derogatory nickname for the Holy Temple Garment worn by temple-attending members of The Church of Jesus Christ of Latter-day Saints. The formal name of the temple garment is "the Garment of the Holy Priesthood." It is similar in meaning to the tzitzit worn by Jews. The Jewish undergarment has knotted tassels at the lower hem, with 613 knots representing the Mosaic laws. The Mormon undergarment has four tiny sewn-in symbols representing one's followership of Jesus Christ and that one should live righteously.
Some people snidely refer to the Mormon garment as "magic underwear," because the Mormon temple garment is "protective." The protection inferred in the wearing of "Mormon underwear" is, however, spiritual. As a reminder of temple covenants, which are covenants to live righteously and keep God's commandments, "Mormon underwear" help Mormons build a spiritual "hedge" to keep out the "destroyer" — Satan. Satan only has power over us to the extent that we invite him into our lives.
"Mormon underwear" also encourages modesty in those who wear "garments," as they are usually called by Mormons. For men, garments come in two pieces, bottom and top. The top looks like a men's tee-shirt and comes in various fabrics for comfort and climate considerations. There are special garments for the military, which look like military underwear, but contain the temple symbols. Military garments may be black or khaki, but otherwise, all garments are white. The bottoms for men look like jockey shorts, but they come down to the knee. Thus, a Mormon man who has made temple covenants, will wear longer-style Bermuda shorts in warm weather, and won't wear a sleeveless tee-shirt except when playing sports. (Mormons don't wear garments while playing sports, or engaging in other activities, such as swimming or dance, but wear them to and from the beach or gym, if possible.)
Garments for women also come in bottoms and tops in various fabrics and styles. Again, they are always white. The neckline of the tops follows the typical bra-line, but there are cap-sleeves on all styles. Thus, a woman who has been endowed in the temple will not wear sleeveless dresses or blouses. Garment bottoms usually come to the knee, but there are longer bottoms to wear under long pants, if desired. Thus, a Mormon woman who has been through the temple will not wear shorts or mini-skirts.
"Mormon underwear" is not to be altered to suit the styles of the day. The cut of Mormon temple garments has changed over the years, however, just for that reason — in pioneer times, temple garments had long sleeves and longer legs.
Temple Garments as "the Armor of God"
Elder Carlos E. Asay said the following:
- ...we are engaged in a life-and-death struggle with forces capable of thrashing us inside out and sending us down into the depths of spiritual defeat if we are not vigilant....Such threatening influences, along with other imminent dangers, constitute “the wiles of the devil” (Eph. 6:11) against which we must stand in these “perilous times” (2 Tim. 3:1)....
- This garment, worn day and night, serves three important purposes: it is a reminder of the sacred covenants made with the Lord in His holy house, a protective covering for the body, and a symbol of the modesty of dress and living that should characterize the lives of all the humble followers of Christ.
- The piece of armor called the temple garment not only provides the comfort and warmth of a cloth covering, it also strengthens the wearer to resist temptation, fend off evil influences, and stand firmly for the right.
Temple Garments as a Reminder of Covenants
Again from Elder Carlos E. Asay:
- I like to think of the garment as the Lord’s way of letting us take part of the temple with us when we leave. It is true that we carry from the Lord’s house inspired teachings and sacred covenants written in our minds and hearts. However, the one tangible remembrance we carry with us back into the world is the garment. And though we cannot always be in the temple, a part of it can always be with us to bless our lives.
- Don’t forget that the word garment is used symbolically in the scriptures and gives expanded meaning to other words such as white, clean, pure, righteous, modesty, covering, ceremonial, holy, priesthood, beautiful, perfection, salvation, undefiled, worthy, white raiment, shield, protection, spotless, blameless, armor, covenants, promises, blessings, respect, eternal life, and so forth. All of these words occupy special places in the vocabularies of people sincerely essaying to become Saints.
- Of one choice group of believers, it is written, “Thou hast a few names even in Sardis which have not defiled their garments; and they shall walk with me in white: for they are worthy. “He that overcometh, the same shall be clothed in white raiment; and I will not blot out his name out of the book of life, but I will confess his name before my Father, and before his angels” (Rev. 3:4–5). How wonderful it would be if all Church members walked with God in white and were numbered with the Saints in Sardis!
The History of Temple Garments
- The scriptures contain many references to the wearing of special garments by the ancients. Prior to their expulsion from the Garden of Eden, Adam and Eve were clad in sacred clothing. We read: “Unto Adam also and to his wife did the Lord God make coats of skins, and clothed them” (Gen. 3:21).
- They received this clothing in a context of instruction on the Atonement, sacrifice, repentance, and forgiveness (see Moses 5:5–8). The temple garment given to Latter-day Saints is provided in a similar context. It is given to remind wearers of the continuing need for repentance, the need to honor binding covenants made in the house of the Lord, and the need to cherish and share virtue in our daily living so that promised blessings may be claimed.
- Moses was commanded to place holy garments and priestly vestments upon Aaron and others, thus preparing them to officiate in the tabernacle. Said the Lord to Moses, “And take thou unto thee Aaron thy brother, and his sons with him, from among the children of Israel … and thou shalt make holy garments for Aaron thy brother for glory and for beauty … that he may minister unto me in the priest’s office” (Ex. 28:1–3).
- References to Aaron’s clothing and the vestments of the priesthood worn by selected leaders in Old Testament times are accompanied by expressions such as “precious garments,” “glorious garments,” “garments of honor,” “coats of glory,” and “garments of salvation.” 3 These expressions may apply more particularly to the raiment worn by those who officiated in tabernacle or temple rites; nevertheless, these descriptive words also apply to the sacred clothing worn on a daily basis by those “who call themselves by [God’s] name and are essaying to [become] saints” (D&C 125:2). The honor, glory, and precious nature of sacred garments, whether worn only in the temple or in everyday life under street clothes, transcends the material of which they are made. Their full worth and beauty is appreciated and regarded as precious or glorious when viewed through the “eye of faith” (Alma 5:15). 
Members of the Mormon Church cringe when the sacred temple garment is held in derision. Most members have never heard deriding comments about the religious vestments of other faiths, probably because no one derides them, out of respect. Again, what is disrespectful when done to friends of other faiths, seems to be tolerated when the criticism is aimed at Mormons. Mormons request some respect of their sacred and holy worship, and the vestments required for that holy worship. They request that you refrain from calling Mormon temple garments "Mormon underwear." Now that you have read this article, you will know better, and you can gently correct your friends.
Please also help others understand that nothing impure goes on in Mormon temples. A Mormon temple is a house of God, a place of light and truth.