Emperor Huizong was a great connoisseur of tea, with masterful skill in the art of tea ceremony. He often engaged in tea tasting and tea competitions with his subordinates at the Song imperial court. Emperor Huizong's favourite was An Ji Bai Cha. (He wrote that what he loved was "Bai Cha." This should not be confused with the tea currently known as "White Tea," but was rather "a Green Tea which had the color of white jade".) In the Treatise on Tea, Emperor Huizong provided the most detailed, vivid and masterful description of the Song dynasty technique of tea spotting. The Emperor also laid down seven criteria for tea competitions.
The Treatise on Tea is a key document for understanding the most sophisticated tea ceremony in Chinese history. It stands as the monumental treatise on tea after Lu Yu's The Classic of Tea (c. 760-780).