The doctrine of God's glory encompasses the greatness, beauty, and perfection of all that he is.
In everything that he is and in everything that he does, God is greater than human description. Every attribute and action of God is stunningly beautiful in every way. Each characteristic of God and every accomplishment from his hand is totally perfect. This is what we mean when we talk about God's glory.
The stunning reality of this universe is that there exists One who is the greatest, the most beautiful and the most perfect in every way. God is gloriously great, gloriously beautiful and gloriously perfect. There is none like him; he has no rivals, and no valid comparisons can be made to him. He is the great Other, in a category of his own beyond our ability to estimate, understand or describe.
Every part of God is glorious in every way possible; there's nothing more to be said. And because God is glorious in every possible way, he alone stands in this vast universe as the only One who is worthy of the worship, surrender and love of every human heart.
- Paul David Tripp
“The glory of God is the infinite beauty and greatness of God’s manifold perfections.” - John Piper
"The holiness of God is, I think, His being in a class by Himself in His perfection and greatness and worth. His perfection and His greatness and His worth are of such a distinct and separated category—we have been taught that holy means separate—that He is in a class by Himself. He has infinite perfections, infinite greatness, and infinite worth... His holiness is what He is as God that nobody else is. It is His quality of perfection that can’t be improved upon, that can’t be imitated, that is incomparable, that determines all that He is and is determined by nothing from outside Him. It signifies His infinite worth, His intrinsic, infinite worth, His intrinsic, infinite value... The glory of God is the manifest beauty of His holiness. It is the going public of His holiness. It is the way He puts His holiness on display for people to apprehend. So the glory of God is the holiness of God made manifest." - John Piper
"His glory is the open revelation of the secret of his holiness." - John Piper
"The holiness of God is his concealed glory. The glory of God is his revealed holiness." - John Piper
"The glory of God is the invisible qualities of God made visible." - John Piper