In Aztec civilization mythology, before chaos had begun to unfold, the gods gathered before a fire. The god Huitzilopochtli threw himself into the flames and burned himself, becoming the sun and ushering in the age of mankind.
Huitzilopochtli was the sun god and the god of war.
The Aztecs believed that whenever the sun set, the sun god died. Blood and the heart were the most precious things in a human body, known as the "Eagle Cactus." Only sacrifices of blood and hearts could resurrect the sun god and make the sun rise each day.
During a sacrifice, the offering would be brought atop a pyramid-shaped temple and laid upon the sacrificial stone. Four people would seize its limbs and stretch it out completely.
Then the offering would drink a cup of anesthetic brewed from herbs, relaxing its body and conforming to the curve of the sacrificial stone, baring its chest fully before the priests.
The priests would step forward holding sharp flint blades and perform the sacrificial ritual.
The executioners understood the structure of the human body extremely well and could locate every organ. With practiced skill, they would cut across the ribs, reach inside to seize the still-beating heart, swiftly tear it out, and raise it toward the sky with both hands as an offering to Huitzilopochtli, the sun god.
Afterward, the heart would be placed in an eagle-shaped dish and burned.
In the Aztecs' understanding, an eagle spirit would then fly down from the sky, carry away the soul of the heart, fly back into the heavens, and offer it to the sun god as food. The soul of that heart would remain with the sun god forever.
Human sacrifice was a daily necessity. Once the heart had been burned as an offering, the head would also