This, then, is the precise nature of the compact between Mexican man and his gods, Do ut des, “Give us rain, and we shall give you blood.” Once this is understood the basic nature of Mexican religion becomes clear, and all the later additions of theology and priestly invention can be viewed as mere excrescences and ornaments upon the simple architecture of the temple of the rain-cult.
THE LATER ELEMENTS OF MEXICAN RELIGION
The evolution of a higher cultus is frequently identified with a more intimate acquaintance with the heavenly bodies, but it is not generally appreciated or understood by students of Comparative Religion that at least two different kinds of conception underlie the general idea. A luminary, sun, moon, or star, may be deified and achieve godhead by reason of striking natural characteristics, or, on the other hand, it may be identified with some god already known. Thus Mexican myth, as related to Sahagun by the natives, asserted that the gods met at Teotihuacan and told how two of their number, Nanahuatl and Tecciztecatl, sacrificed themselves by leaping into a great fire, becoming the sun and moon respectively. The remaining gods, sacrificing themselves also, “conferred life upon the stars,” that is they became identified with the several stellar constellations, becoming known as the Centzon Mimixcoa and Centzon Uitznaua, or “Four hundred Northerners” and “Four hundred Southerners,” as they occupied the sky on its northern or southern side.22
Although this myth and a version of it current at Texcuco and given by Mendieta in his Historia Ecclesiastica23 both represent Nanahuatl as the sun-god, he was not so known in Mexican popular religion and priestly practice, and was indeed a form of the god Xolotl, a deity of obscure characteristics. Tecciztecatl certainly was regarded as the moon-god, but the solar luminary was known as Tonatiuh or Piltzintecutli. As has already been stated, there are sound reasons for the belief that the solar