God’s “glory” is how we describe the sum effect of all of his attributes: Grace, truth, goodness, mercy, justice, knowledge, power, eternality—all that he is. Therefore, the glory of God is intrinsic, that is, it is as essential to God as light is to the sun, as blue is to the sky, as wet is to water. You don’t make the sun light; it is light. You don’t make water wet; it is wet. In all of these cases, the attribute is intrinsic to the object.
In contrast, man’s glory is granted to him. If you take a king and take off all his robes and crowns and give him only a rag to wear and leave him on the streets for a few weeks, when put next to a beggar you’ll never know which is which. Because there is no intrinsic glory. The only glory a king has is when you give him a crown and a robe and sit him on his throne. He has no intrinsic glory.
That’s the point. The only glory that men have is granted to them. The glory that is God’s is his in his essence. You can’t de-glory God because glory is his nature. You can’t touch his glory. It cannot be taken away. It cannot be added to. It’s his being.