In this sermon, Mel Purvis focuses on Jesus' command that His disciples wait in Jerusalem for "the promise of the Father"—the baptism with the Holy Ghost. Purvis explains that although the disciples had already walked with Jesus, believed in Him, witnessed His resurrection, and received a measure of the Spirit (John 20:22), they were still completely unprepared for ministry until the Spirit came upon them in power.

He shows the distinction between the Spirit's work in salvation and the Spirit's empowerment for service. Using the Upper Room as a model, he emphasizes obedience, unity, expectancy, and surrender as prerequisites for receiving the fullness of the Spirit. The sermon warns believers not to attempt spiritual work in natural strength and calls for renewed seeking of God's power.