In Exodus 33:18, Moses requests God to display His glory. How did God respond to that request? He preached him a sermon on His name! Or we could say that He expounded before Moses on the third commandment. What we have here is probably just the barest summary of what God said—the notes, as it were, of what He talked about more fully. He likely preached him a sermon on eleven names of God: Yahweh, El, the Merciful One, the Gracious One, the Longsuffering One, the Almighty, the Bountiful One, the True One, the Preserver of Abundance, He Who Takes Away Iniquity, and He Who Visits Iniquity.
What He did before Moses was rehearse His nature. It was so encouraging to Moses, because he knew then that the children of Israel would not be abandoned—that God would be with him—because of what He is. He would remain with them, though not because Israel deserved His presence in any way, shape, or form—every single one of them deserved to be dead! But because God is God, He would continue through with His purpose, and these names exemplified what He would be doing.
So God did not give Moses a vision of His majesty and power, but of His character. The glory of God is the manifestation of His nature, of His character, of His way of relating to His creation—especially to His children. His names are signposts of His nature. They are reminders to us of what we can expect Him to do. That is why Moses was so encouraged.