How does the author use foreshadowing in Water Margin?

The story of Water Margin begins when Marshal Hong Xin is sent to a Taoist monastery to request a cure for a plague currently being suffered by the people of the Eastern Capital. Hong causes problems when he commands the monks of the monastery to free the 108 demons being held captive in the Suppression of Demons Hall. This foreshadows problems when these 108 stars, 36 stars of heavenly spirits and 72 stars of earthly spirits, become the bandits of Liangshan Marsh.