Being filled with the Spirit is simply this - having my whole nature yielded to His power. When the whole soul is yielded to the Holy Spirit, God Himself will fill it.
Andrew MurrayThe Lord gave the wonderful promise of the free use of His name with the Father in conjunction with doing His works. The disciple who lives only for Jesus' work and kingdom, for His will and honor, will be given the power to appropriate the promise. Anyone grasping the promise only when he wants something very special for himself will be disappointed, because he is making Jesus the servant of his own comfort. But whoever wants to pray the effective prayer of faith because he needs it for the work of the Master will learn it, because he has made himself the servant of his Lord's interests.
Andrew Murray