I've been thinking about that scene from Exodus, when God (in the burning bush) says to Moses: "I am who I am."
Why didn't God just say God's name? Yet I think about this scene as related to the first commandment, "You will have no other gods before me."
Many idols in our lives try to convince us of their goodness, their salvific properties, their awesomeness and our intense need for whatever it is that they offer. These products, people, places promise to make us relevant, cause our story to endure, cement our relationships. But this is all just wind and it eventually returns to ashes.
The only solid rock we have is the great I AM. God doesn't need to announce Godself or what God's profession is because God simply is. God meets the gap where others fall short. God's relationship with us isn't broken through God's actions. God's promises are so solid, they could be insured by Lloyd's of London.
The gods of this world prey on our fears. The God who made the world knows our fears and hears our prayers.
God told Moses the name "I am" because there was no other answer that would seem really adequate when one is watching a burning bush go unconsumed. God is the God who grants grace to us while we are still sinners. God is the God who comes to us in the elements of the Holy Supper. God is the God whose presence comforts us and whose peace heals us. God is the one true Triune God.