Holy of Holies (LDS Church)
In The Church of Jesus Christ of Latter-day Saints (LDS Church), the Holy of Holies is a room in the Salt Lake Temple wherein the church's president — acting as the Presiding High Priest of the church — enters to act as High Priest of Israel in direct relationship with God, in accordance with the LDS interpretation of the Book of Exodus. Hence, this Holy of Holies in the temple is considered a modern cognate to the inner sanctuary of the Tabernacle and Temple in Jerusalem.
Teachings by LDS Church leaders 
Boyd K. Packer, a member of the Quorum of the Twelve Apostles, has stated that “hidden away in the central part of the temple is the Holy of Holies, where the President of the Church may retire when burdened down with heavy decisions to seek an interview with Him whose Church it is. The prophet holds the keys, the spiritual keys and the very literal key to this one door in that sacred edifice”.
"Most Holy Place" 
Although not a general rule, in certain contexts the term “Holy of Holies” may be synonymous with “Most Holy Place.” The construction "Holy of Holies" is a literal translation of a Hebrew idiom Kodesh Hakodashim ( קֹדֶשׁ הַקָּדָשִׁים ), referring to the inner sanctuary of the Tabernacle or Temple in Jerusalem. In the King James Version of the Bible, this sanctuary is always referred to as the "Most Holy Place," which also appears to hold true in the LDS Church book of scripture known as the Doctrine and Covenants.
In church scriptures 
Speaking of the purposes of temples 
"Therefore, verily I say unto you, that your anointings, and your washings, and your baptisms for the dead, and your solemn assemblies, and your memorials for your sacrifices by the sons of Levi, and for your oracles in your most holy places wherein you receive conversations, and your statutes and judgments, for the beginning of the revelations and foundation of Zion, and for the glory, honor, and endowment of all her municipals, are ordained by the ordinance of my holy house, which my people are always commanded to build unto my holy name."
First Presidency receives the oracles for the church 
"I give unto [Joseph Smith] for counselors my servant Sidney Rigdon and my servant William Law, that these may constitute a quorum and First Presidency, to receive the oracles for the whole church".
Biblical reference to the Holy of Holies and the oracle 
- Speaking of Solomon’s Temple
"And he built twenty cubits on the sides of the house, both the floor and the walls with boards of cedar: he even built them for it within, even for the oracle, even for the most holy place."
See also 
- Exodus 25:22
- Buerger, David John. The Mysteries of Godliness. Signature Books (November 2002). Last accessed 2006-11-16 (excerpts only online).
- Boyd K. Packer (1980). The Holy Temple (Salt Lake City, Utah: Bookcraft) p. 4.
- James E. Talmage (1969). The House of the Lord (Salt Lake City, Utah: Bookcraft) pp. 192–194.
- Personal Writings of Joseph Smith, 1 May 1842, pp. 119–120.
- Doctrine & Covenants 124:39 (emphasis added).
- Doctrine & Covenants 124:126 (emphasis added).
- 1 Kings 6:16 (emphasis added).