In the last post, we took a look at the “birth” of the LDS sacrament in Oliver Cowdery’s 1829 Articles of the Church of Christ. That document was the predecessor of the 1830 Articles and Covenants of the Church of Christ, which eventually became what is today section 20 of the Doctrine and Covenants.
In this post, we’re going to take a look at why Oliver Cowdery chose to use Moroni’s liturgy as the liturgy for the sacrament for the new church.The Parent: Moroni’s Liturgy
If the Articles are the Sacrament’s birth, then the liturgy that Moroni recorded is the parent. Most church members readily recognize that the sacrament prayers set forth in section 20 are identical to those recorded in Moroni, in what is now chapters 4 and 5 (with the exception that the Book of Mormon has the archaic “hath” where the Doctrine and Covenants has the more contemporary “has”). That’s no mystery: it’s where Oliver Cowdery got the prayers.
In taking the the sacrament prayers from Moroni, Oliver Cowdery wasn’t just lifting text from the Book of Mormon because he was lazy, he was following the instruction given to him in the June 1829 revelation now canonized as section 18. When Joseph Smith dictated that revelation, he and Oliver Cowdery were weeks away from finishing the Book of Mormon translation, and it had been about a month since they had translated 3 Nephi and had received the Aaronic priesthood. “[T]he building up of the Church,” that is, baptizing believers and leading them in worship, is a major theme in 3 Nephi (see, e.g., 3 Nephi 11:21-28, 40; 3 Nephi 18, 3 Nephi 27). And that theme was what inspired Joseph Smith and Oliver Cowdery to seek instruction regarding the authority to baptize, which instigated the restoration of that authority. With that authority restored, the June 1829 revelation naturally provided further “instructions relative to the building up of the church.” (This is a quote from the section heading; it also appeared in the heading to that section in the Book of Commandments in 1835).
The revelation opens by telling Oliver that he knows that “the things that [he has] written [that is, the Book of Mormon] are true” because God has manifest to him by the Spirit that they are true. (See v. 2). It then goes on:
And if you know that they are true, behold, I give unto you a commandment, that you rely upon the things which are written; for in them are all things written concerning the foundation of my church, my gospel, and my rock. Wherefore, if you shall build up my church, upon the foundation of my gospel and my rock, the gates of hell shall not prevail against you. (See vv. 3-5).
Oliver was thus commanded to rely on the Book of Mormon to “build up my church.” He took that commandment seriously; so when he put together what was essentially the predecessor of what would ultimately become constitution of the church, he took the liturgical forms that the church would use word for word directly from the Book of Mormon, including the sacrament prayers, from what is now Moroni chapter 4 and 5.
The sacrament liturgy recorded by Moroni is thus the immediate source for the sacrament prayers that Oliver set in place, which became the sacrament liturgy for the restored church.
Next time: Where did Moroni’s liturgy come from?
 In fact, the entire document relies heavily on the Book of Mormon. The form for ordinations of teachers and priests is also from Moroni, and the baptismal prayer is also taken word for word from 3 Nephi, as well as other passages. See 1829 Articles of the Church of Christ.