Each year the Aztec's had a festival for the sun god, Tepoztecatl (smoking mirror). Tepoztecatl was one of the most feared gods and it was believed that he could destroy the world if he wanted to; because of this there were a lot of festivals in his honor (this is why he is also referred to as the god of music.)
One year before the festival the Aztec's choose the most handsome male prisoner to be sacrificed to Tepoztecatl. This individual was taught to sing, dance and play the flute. For the entire year before the sacrifice, the man was treated like a king. Before the sacrifice he would walk in a parade with four beautiful women.
At the sacrifice the priest would cut open the flute players chest, rip the heart out and offer it to sun.
Hyperhistory, "about Aztec sacrifice", Available: online at: http://www.hyperhistory.net/apwh/essays/facts/f4sacrificera.htm
nbbroelm, " The Aztec Sun God Tezcatlipoca", Available: online at: http://www.loyno.edu/~nbbroelm/aztec.html