Jonathan Edwards here speaks of God's pleasure in creation:
"the pleasure God hath in those things which have been mentioned, is rather a pleasure in diffusing and communicating to, than in receiving from, the creature. Surely, it is no argument of indigence [i.e. neediness] in God that he is inclined to communicate of his infinite fullness. It is no argument of the emptiness or deficiency of a fountain, that it is inclined to overflow."
God creates from fullness not need. His glory is not about demanding but giving. From the Father's eternal begetting of the Son comes the logic of creation's in-time manufacture. Creation is not the first time God has to relate to another. Instead, creation finds its origin in His already-outgoing nature.
Creation is, therefore, birthed in self-giving love, not willed out of any necessity. We can rest assured - God has not called us forth to gain from us, but to give to us. In this sense we are "created for His glory." We exist precisely because it is His glorious nature to give life.
The Father has eternally poured life and blessings onto and into His Son by the Spirit. He continues to express this glory by pouring out life to the world through His Christ. In this way creation will be glorified, as the Lord gives of Himself, even to the depths of the cross.
Or to say it how Jesus did: "He who loses his life will find it." (Luke 17:33). First it is God who finds His life in losing it. He is who He is as He gives Himself away for the world. Therefore Jesus does not call us into anything He hasn't eternally and originally been part of. But now, through His invitation, we get to share in it. Glory!