Then [God] said to him, “I am יהוה who brought you out from Ur of the Chaldeans to assign this land to you as a possession.”
Genesis 15:7 (The Contemporary Torah, JPS 2006)
The Midrash contains a fascinating story about Abram, suggesting that Nimrod (king of Babylon) threw Abram into a blazing furnace for not worshipping his idol. “Ur” means “flame.”
He was in the fire, but not consumed by it.
The rabbis say that Genesis 15:7 is the first time God tells Abram His name.
Later, when God meets Moses, He presents His name and another fire, this time on a bush that is not consumed.
Perhaps this is how Moses remembers the covenant God made with Abram: these are intentionally linked stories. God preserves us, even through the fire that should consume us.