The central message of this sermon is that true faith, or a lack thereof, has a profound impact on how God's power and presence manifest in our lives. The speaker argues that it's not about God gaining or losing power, but rather about our involvement and participation in the process of receiving His blessings. This idea is illustrated through Jesus' experience in Nazareth, where He was amazed by the unbelief of the people and therefore did only a few miracles, whereas in Gennesaret, where faith was present, He poured out healing on many. The speaker draws from this biblical example to emphasize that our own faith or lack thereof affects what God does or doesn't do in our lives, and that we are not "in charge" but rather participants in the process of receiving His power and blessings.