Chapter 7 explores the relationship between joy and surrendering to Christ, emphasizing that true joy comes from selflessness and following Jesus' teachings. It raises questions about personal surrender, highlights the joy associated with living out one's God-given purpose, and contrasts 'tweener' believers who struggle with full surrender to Christ. Chapter 8 discusses the significance of purpose in achieving joy and the impact of living an underpurposed life, suggesting that fulfillment comes from service and focusing on eternal goals.