Watching the enthusiastic departure of Lao Gui, Lu Yu himself was unsure whether his actions were right or wrong. After all, it involved Journey to the West, and although he had the knowledge of a past life to draw on, this was, in the end, a real world. So, he dared not make any guarantees—perhaps there was another Lao Gui cultivating in secret within the Tongtian River.
However, since Lao Gui had sought benevolence and received it, whether the matter was successful or not, it could be considered to have fulfilled his wish. What made Lu Yu curious was the towering sin that clung to Lao Gui; he wondered what sort of heaven-angering and people-resenting deeds his ancestors had committed to leave such a terrifying legacy of sin for their descendants.
It probably involved some major events from Ancient Times, but with the scant information Lu Yu had at the moment, he simply could not deduce anything.