Final answer:
The Sacramentary, also known as the Roman Missal, is a liturgical book in the Roman Catholic Church. It contains the prayers used by the priest at the altar during Mass. The book assists with the orderly delivery of the Mass.
Step-by-step explanation:
The Sacramentary, also referred to as the Roman Missal, is an important liturgical book in the Roman Catholic Church. The subject of this question is Religious Studies. The prayer book referred to in the question is called a Sacramentary, and it contains the prayers of the Mass for the use of the priest at the altar. It is a significant liturgical book in Christian worship, specifically in the Roman Catholic Church.
It contains the prayers of the Mass used by the priest at the altar, including the proper prayers for each Sunday, as well as special feasts and observances. The book assists with the orderly delivery of the Mass and is typically kept on the altar for the priest's reference during services.
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