In this sermon, the preacher focuses on the importance of righteousness, peace, and joy in the Holy Ghost as the true essence of the Kingdom of God. He references Psalm 51, where David, a backslider, repents for his sins of adultery and murder. The preacher emphasizes the need for discipline and a clean heart, as well as the danger of not abiding in Jesus and keeping His commandments. He also addresses the topic of eternal security and refutes the idea that salvation can be lost, emphasizing that salvation is from sin and is evidenced by a transformed life.