In Journey to the West, why didn't the monster eat directly after catching the Tang Priest, and why didn't he wash it?

The ancients were superstitious, so the immortals of the ancients were naturally superstitious. Superstition says that in case of major events, you should predict in advance or choose an auspicious day in order to get God's blessing. If the Tang priest is caught, he won't eat it directly. Maybe there is a factor of waiting for a good day. Some goblins who want to eat the Tang Priest all know that the Monkey King is the great disciple of Tang Priest, and they have heard the story of the Monkey King's havoc in Heaven more or less.

They have lived for hundreds of years, without a powerful magic weapon, and practice on their own. If you want to live a long life, you must know how to seek good fortune and avoid evil. When these people caught the Tang Priest, they didn't want to eat it, but they didn't dare to eat it. If you eat the Tang Priest, the Monkey King will kill him immediately. If you don't eat, you can barely live for hundreds of years I have long heard that the Monkey King, a disciple of the Tang Priest, will be beaten if he doesn't eat. Only by defeating the Monkey King can we stop eating well. So they waited for a few days, washed and prepared first, and as soon as Wukong died, they began to eat.

The main purpose of this kind of monsters is not to eat Tang monk's meat, but to love, such as Kuimu Wolf, to lad, such as carp essence and deer essence, to disgust the Monkey King, such as Huangmei monster, and some monsters are simply looking for trouble, such as King Jinjiao, King Yinjiao, King Qingniu essence and so on! They only pay lip service to the Tang monk's meat, or they are deliberately angry with the Monkey King, mainly to test the Buddhist scriptures team. They don't really want to eat Tang Priest's meat, so they won't really eat it, but they are holding Tang Priest and the Monkey King to play hide and seek!

Journey to the West shows us a world where the law of the jungle prevails. In this world, the Tathagata Buddha standing at the top of the food chain needs to be controlled by the Jade Emperor. How can a little demon king avoid life and death?