1. Yü-ching, the heaven of pure jade, inhabited by Yüan-shih t'ien-tsun, one of the highest deities of religious Taoism (tao-chiao). He created heaven and earth, and at the start of each new age, he gives Ling-pao ching to subordinates who instruct humans from it in the way of Tao.
2. Shang-ch'ing, the heaven of purity, ruled by Ling-pao t'ien-tsun. He is the guardian of Ling-pao ching, and regulates time and the balance of yin and yang.
3. T'ai-ch'ing, the heaven of highest purity, ruled by Tao-te T'ien-tsun, the guardian of tao and te. He is identified with Lao-tzu.
"San-ching." The Concise Oxford Dictionary of World Religions. . Encyclopedia.com. (October 24, 2018). https://www.encyclopedia.com/religion/dictionaries-thesauruses-pictures-and-press-releases/san-ching
"San-ching." The Concise Oxford Dictionary of World Religions. . Retrieved October 24, 2018 from Encyclopedia.com: https://www.encyclopedia.com/religion/dictionaries-thesauruses-pictures-and-press-releases/san-ching