Purple Qi Yuanjun, whose full name is "Jade Purity Holy Ancestor Purple Qi Yuanjun", is said to be the mentor of the Great Emperor Zhenwu. Most of the major temples and monasteries on Wudang Mountain have built the Yuanjun Hall, where a sitting statue of the Purple Yuanjun is enshrined. According to the "Zhenwu Benzhuan Miaojing", the origin of the Jade Purity Holy Ancestor, the Purple Qi Yuanjun, is that she is the incarnation of the Primordial Heavenly Lord. When traveling in the Kingdom of Jingle, he was given the title of Lord Ziyuan and imparted the secret of the Supreme Harmony and Jade Void to Emperor Xuan Di, teaching him the Great Precepts of the highest grade of wisdom. Ancient books such as "Jiangbi Shilu" record the story of Ziyuan Jun's liberation of Zhenwu. It is said that Zhenwu was born into the Kingdom of Jingle as the crown prince, but he was unwilling to inherit the throne and was determined to study the Tao. The crown prince's actions moved Ziyuan Jun, who bestowed upon him the Supreme Path of Wuji. At the age of fifteen, the Crown prince bid farewell to his parents and went to Wudang Mountain to practice. After several years, he failed to achieve enlightenment and left the mountain to return to lay life. At this moment, Lord Ziyuan transformed into an old nun, holding an iron pestle and grinding it on a stone. The Crown Prince was very surprised when he saw this and then realized it, returning to the mountain to cultivate. Later generations built a temple and erected a statue at the place where Lord Ziyuan ground his needle to worship him. The temple gate is called "Needle Grinding Well", which is one of the scenic spots on Wudang Mountain. The Crown Prince practiced on Wudang Mountain for forty-two years and achieved enlightenment. Ziyuan Jun transformed into a beautiful woman to test the crown prince. The Crown prince was not bewitched. Ziyuan Jun said, "The Great Way has been established. Let the Five Dragons hold the Crown Prince and lift him to heaven." The Jade Emperor bestowed upon him the title of "Supreme God of Xuantian".