This qualitative research study explores the role of the sermon in corporate Nazarene worship. The context of this study is located with the Christian, Protestant, evangelical, Wesleyan theological tradition as expressed through the Church of the Nazarene in Australia. The church is briefly described from a Wesleyan perspective. Seven features are identified as historically important within the worship experience of Nazarenes; Biblically centred, centrality of the sermon, connection with Christian tradition, the preacher's life, encounter with self and the divine, community, and practical and relevant to present life. The conceptual lens through which the worship experiences are described is Cultural Historical Activity Theory (CHAT), as primarily articulated by Yrjö Engeström (1999). The philosophical roots of CHAT and the concept of activity are described along with the structure of activity. Additionally, the compatibility of Wesleyan theology with the conceptual understanding of CHAT is presented. The interactive context of Nazarene worship is one of the compelling reasons given for using CHAT as the conceptual base for this study. Three corporate Nazarene worship experiences in three different Nazarene congregations are examined in detail using four research methodologies; namely, video taping, video stimulated recall interviews, focus groups, and observation reports. The data gathered is by way of transcriptions based on the video taping of the sermons, stimulated recall interviews and focus groups and is managed by use of the NUD*IST (5) computer program. The observation reports are used to gain insight into specific context issues. Nazarene worship is then mapped by relating the features found to be historically important in Nazarene worship to elements of the activity system. The role of the Bible, the sermon, Christian tradition, the preacher's life, the church community, personal encounter, divine encounter, and the application and the call to decision are identified in CHAT terms. The focus of this study is within Steps 1 and 2 of Engeström's (2000) expansive development cycle. Through the mapping of Nazarene worship, tensions are identified and their possible sources explored. The tensions of confrontation versus care, creation of a quiet, meditative environment versus noisy, dynamic environment, planning versus spontaneity, and individual versus community orientation are all explored in turn. Possibilities for resolution of these tensions are suggested as a means of guiding the continued development of the activity of Nazarene worship. Possible resolution of these tensions includes the change of the focus of sermons from confrontation to empowerment, the change of the structure of sermons to encompass the visualisation of the change sought, the change of the perceptions of the preacher to one of a sojourner, and the cultivation of spontaneity within sermon delivery. The static nature of the sermon as an instrument in both the sermon's historical development and the development of the corporate worship experience points to the need for the development of the sermon as a more flexible instrument. These conclusions have implications for the teaching of preaching in schools preparing Nazarene preachers. This study contributes to the conceptual basis for the ongoing development of clergy in their preaching ministry. This study has also made visible the difficulty of applying the conceptual framework of CHAT to the complex situation of corporate Nazarene worship experience. While conceptually it may be possible to differentiate between elements within an activity system, their practical distinction is less precise. This imprecision can create confusion especially at the tertiary and quaternary levels of contradictions and may need more precise articulation of the interactions within the activity system as well as between activity systems.