Nammyeong Cheon Hwasang song jeungdoga (Song of Enlightenment with Commentaries by Buddhist Monk Nammyeong)

The postface written in 1239 by Choi Yi, Duke of Jinyang, at the end of this book states that Nammyeong Cheon Hwasang song jeungdoga (Song of Enlightenment with Commentaries by Buddhist Monk Nammyeong) was printed using woodblock carved in relief based on the original movable metal type version. Thirteenth-century was a very chaotic period in Goryeo history due to the Mongolian invasions. It is possible to infer that movable metal printing was not a new phenomenon at that time, but rather, it was already a popular printing method in Goryeo from the fact that the people of Goryeo printed books with movable metal type even during such trying circumstances.