The Book of Malachi, the last book of the Old Testament, occupies a distinctive position in Latter-day Saint theology, serving as a bridge between ancient prophecy and latter-day revelation. Malachi’s emphasis on covenantal faithfulness, the purification of God’s people, and the promise of Elijah’s return has profound implications in the teachings of The Church of Jesus Christ of Latter-day Saints. Moreover, Malachi’s words are uniquely adapted and expanded in the Book of Mormon and modern revelation, reinforcing their centrality to Latter-day Saint beliefs about priesthood authority, temple work, and the gathering of Israel.

Malachi, written post-exile during the Persian period (likely in the 5th century BCE), addresses Israel’s religious and moral failings, particularly emphasizing covenantal obligations. It admonishes the people to return to God through sincere worship, proper sacrifices, and reverence for divine ordinances. Latter-day Saints regard Malachi as a key prophetic text, emphasizing its foretelling of events and principles foundational to the Restoration of the gospel.

1. Covenantal Faithfulness
   Malachi’s call to honor God by observing the covenant resonates with the Latter-day Saint emphasis on keeping sacred promises made at baptism and in the temple. The prophet rebukes corrupt priests and unworthy offerings (Malachi 1:6–14), a reminder of the sanctity required in all ordinances and worship. Malachi also underscores the importance of tithing (Malachi 3:8–12), a principle reaffirmed in modern scripture (e.g., Doctrine & Covenants 119) as essential to spiritual and temporal blessings.
2. Purification and Refining
   The imagery of the refiner’s fire and fuller’s soap (Malachi 3:2–3) is a prominent motif in Latter-day Saint teachings about personal sanctification. This metaphor is often used in the context of spiritual preparation for the Second Coming of Jesus Christ and reflects the sanctifying power of temple ordinances and the Holy Spirit.
3. The Role of Elijah and the Sealing Power
   Malachi 4:5–6 prophesies the coming of Elijah before the "great and dreadful day of the Lord," foretelling his role in turning the hearts of the fathers to the children and vice versa. This passage is foundational to Latter-day Saint doctrine. It was fulfilled, as recorded in Doctrine & Covenants 110:13–16, when Elijah appeared to Joseph Smith and Oliver Cowdery in the Kirtland Temple in 1836, restoring the sealing power and priesthood keys necessary for temple work. This connection ties Malachi's prophecy directly to modern Latter-day Saint practices of family history and temple ordinances.

The Book of Mormon adapts and expands Malachi’s text, emphasizing its importance to the House of Israel in the latter days. In 3 Nephi 24–25, the resurrected Christ quotes Malachi’s words to the Nephites, providing additional doctrinal context. This inclusion underscores the eternal relevance of Malachi’s teachings and confirms their applicability beyond their original historical setting.

1. Emphasis on the Lord’s Messenger
   The mention of “the messenger” in Malachi 3:1, interpreted as John the Baptist, prefigures the restoration of the priesthood and the preparatory role of forerunners in the dispensation of the fulness of times.
2. Expansion of the gathering of Israel Theme
   The repetition of Malachi’s words in the Book of Mormon serves as a witness of God’s covenantal promises to gather His people, particularly the descendants of Lehi, into one fold through the restored gospel.
3. Preparation for the Final Judgment
   Christ’s use of Malachi 4:1–2 to teach about the destruction of the wicked and the healing power of the Son of Righteousness reiterates the centrality of personal righteousness and divine mercy in Latter-day Saint theology.

The importance of Malachi extends beyond the Bible and the Book of Mormon into modern Latter-day Saint scripture. Doctrine & Covenants 2, the earliest recorded revelation to Joseph Smith, quotes Malachi’s prophecy of Elijah, linking it to the Restoration of the gospel and the work of redeeming the dead. Additionally, Joseph Smith’s teachings frequently return to Malachi 4:5–6 as a cornerstone of temple doctrine and priesthood authority.

Malachi’s writings serve as both doctrinal anchors and practical guides for Latter-day Saints. His calls for tithing and covenantal fidelity inform individual and collective practices, while his prophecies of Elijah underscore the eternal nature of family relationships and the salvific work conducted in temples. The repeated emphasis on preparation for the day of the Lord inspires vigilance and faithfulness among Latter-day Saints.

The Book of Malachi occupies a central role in Latter-day Saint theology, bridging ancient prophecy with modern restoration. Its messages about covenantal faithfulness, divine refinement, and the restoration of priesthood keys through Elijah provide both theological depth and practical guidance. Malachi’s words, adapted and reaffirmed in the Book of Mormon and modern revelation, illustrate their enduring significance, confirming that God’s promises to Israel continue to unfold in the dispensation of the fulness of times.