God can accomplish more through one message in the fulness of the Spirit than through hundreds given in the energy of the flesh.
The three representative men of the Bible, the natural, the carnal, and the spiritual - Which are you? Are you living in Egypt, the world and home of the natural man, or in the wilderness, the abode of the carnal? ... Are you already through the wild...
The fulness of the Spirit is not a question of our getting more of the Holy Spirit, but rather of the Holy Spirit getting more of us.
And they continued steadfastly (Acts 2:42) - That is to say, they did not backslide. The real reason there are so many backsliders is because there are so many who have never had a forward slide to Jesus Christ.
And believers were the more added to the Lord, multitudes both of men and women (Acts 5:14)- So not only was there Holy Ghost boldness and Holy Ghost power and Holy Ghost conviction, but also Holy Ghost conversions.
Power in Service - The carnal man can never be used in spiritual service. There is so much of the self life about him that God cannot gain control. The Spirit-filled life is necessary for fruitful Christian service.