Tus!ita Heaven. The fourth of the six heavens of the desire realm. The original meaning of the word tus!ita is "to satisfy." This heaven is a place of preparation where future "buddhas-to-be" teach， practice and await their entry into the physical world. S/a^kyamuni abode there before his birth in the physical world and Maitreya 弥勒 is said to be waiting there now. A lifetime in Tus!ita Heaven is said to be 4，000 years， with each morning and evening of this time being equivalent to 400 years in earth-time. Tus!ita Heaven is one of the six heavens of the desire realm 六欲天.