The Liangyi Hall is an important palace layout on Wudang Mountain. Generally, a parents' hall is built behind the main hall dedicated to the True Warrior for people to pay homage. In Nan Yan, due to geographical limitations and the need to preserve the original Yuan Dynasty stone hall, the designers ingeniously constructed a side gate and built this Parents' Hall, demonstrating the builders' superb conception. The term "Liangyi" first appeared in "Xici" of the I Ching, which states: "The I Ching has Taiji, which gives birth to Liangyi." Here, "two instruments" refer to "Yin" and "Yang". He also said, "Gan is a Yang thing." Kun is a Yin element." "Gan means heaven, and thus is called father." Kun is the earth, thus it is called "Mother". Here, the main meaning of "Liangyi" refers to "parents", and it can also be extended to "heaven and earth", "Yin and Yang", etc. One distinct feature of Wudang Taoism is the requirement for monks to be loyal, filial, trustworthy and sincere. Behind the main halls of each palace and temple in Wudang, there are parents' halls. Although it enshrines the biological parents of Zhenwu, it also teaches every believer and worshipper that respecting and caring for one's parents is a major principle in a spiritual life and one of the most fundamental beliefs and behavioral norms of Wudang Taoism.