Thesis (Ph.D. (Liturgics))--North-West University, Potchefstroom Campus, 2009.During services of the Reformed Churches of South Africa (RCSA), certain psalms and Biblical hymns are used frequently, while others are almost never used. The objective of this study is to determine how the Psalter of 2003 can be used optimally. The model of Zerfass is used for the investigation. The final results of the study are presented in the form of a model that can enrich the optimal use of the Psalter 2003 as means of communication in the liturgy of the RCSA. In Chapters 2 and 3, a basic-theoretical investigation is conducted, with reference to perspectives from Scripture and history. The investigation reveals that music and songs had already played an im...