Jesus' teaching is from God, not His own authority. If anyone wants to do God's will in his heart, he will begin to understand who Jesus is and what God's requirements are. Every believer should be filled with the Spirit, becoming a conduit of His grace to nourish the world. God's re-creation started with the resurrection and continues to flow out and transform the world.
In contrast to the world's man-worshipping glory, John shows us a new category of glory reflected in the cross. John uniquely connects Jesus' suffering with glory. The cross is not the condition of glory. The Cross is God's glory. In giving the Father glory, Jesus reveals the nature of the Father's glory. We're being transformed from one degree of glory to another.
Jesus endured the cross for the joy set before Him. The most mature Christians have often suffered greatly and yet experience great joy. The Comforter helps us and guides us in our persecution. Persecution cements the truth together with the power of the Holy Spirit in the life of the Church.
By our inherited sinful nature, we are blind and deaf; we need to be born again in order for us to hear the voice of the shepherd. Power is the capacity to achieve a purpose. God's purpose is to win a covenant people for Himself. When Christ seemed powerless on the cross, His life was most powerful in accomplishing God's purpose. Jesus is working with the Father for the eternal security of the sheep; we need to listen to Him.