Back when Song Shuhang learned ❮Ksitigarbha's Soul Ferrying Scripture❯, a copy of Ksitigarbha's Soul Ferrying Scripture had appeared in the hands of the 'true self' generated through the ❮True Self Meditation Scripture❯.
Therefore, Song Shuhang guessed that ❮Ksitigarbha's Soul Ferrying Scripture❯ might be something that had originated from the Jingang Temple. Afterward, it ended up in the hands of the western monk, who practiced it until creating his unique 'Soul Ferrying Technique', obtaining that thick light of virtue that now covered his body. It was a matter that had caused much pain to the liver of his teacher, Wu Yinzi—to the point that he couldn't sleep at night properly.
