Why was it believed that the Aztecs greeted Cortés as a deity?

Camilla Townsend:

What really happened when the messengers returned with their report was that Moctezuma sent scouts out to every important town between Tenochtitlan and the coast, and then set up a veritable war room. This is exactly what one would expect him to have done, given his history as a ferociously successful tlatoani who believed wholeheartedly in order, discipline, and information. Years later, a man who had been young at the time remembered: “A report of everything that was happening was given and relayed to Moctezuma. Some of the messengers would be arriving as others were leaving. There was no time when they weren’t listening, when reports weren’t being given.” The scouts even repeated a summary of the religious instruction that was being regularly offered by the Spanish priest and translated by Jerónimo de Aguilar and Marina. When the Spaniards later got to Tenochtitlan and tried to deliver a sermon to Moctezuma, he cut them off, explaining that he was already familiar with their little speech, his messengers having presented it to him in full.