During the Vedic period priests intoned verses, some spontaneous but most carefully crafted according to the strict rules that made Sanskrit so precise and difficult to use. These mantras became formulas, which were memorized to make sure that no error was made in pronunciation, grammar, phrasing, accent, pitch, and so on. Their use in Vedic religion is discussed in chapter 1, “The Vedic or Samhita Period.” The logic of mantra usage in the evolution of Hindu mythology can also be see in chapter 1, “Renunciation, Sacrifice, and Magic.”