The god of life and death, of day and night, of creation and destruction, of male and female existed before everything else, a god without parents, a god without friends. Then this god divided itself into the Lord of Duality and the Lady of Duality. These two mated and were infinitely fruitful. From their children came all gods and living things in heaven and on earth. The Lord of Duality rules over the day; the Lady of Duality rules over the night; and the God of Duality persists in their union.
At the hearth of every home, a fire is always kept for Xiuhtecuhtli. The Turquoise Lord, Xiuhtecuhtli, is the god of fire and the god of time. He is life in death, light in darkness, warmth in coldness, food in famine. He is days and months and years against formless chaotic eons.
Like the family of Abraham in the Hebrew Bible, the Aztecs believed in human sacrifice. I’d say they believed what they were told. They inherited a mythology in which their gods sacrificed themselves for them, and a social structure in which their rulers and their priests made it honorable to sacrifice slaves and war captives.