During the first three millennia BC, the Temple played a central role in urban life, both spiritually and economically. Temples trained the priesthood and thus held the secrets of writing and of the stars. Temples also gave vital economic knowledge to the masses. The rites of the Temple announced the times for planting and for harvest, for flooding and for drought. With a Temple, a city gained stature, commerce, and faith unmatched by any other ancient structure.