Due to the limitation of ancient observation and understanding of the world, the earth is full of all kinds of supernatural forces, and rainbows come and go in a hurry and are erratic. In literary works, the rainbow is regarded as a god who can drink water.

The ancients thought that the rainbow had powerful supernatural power, so it was made into a ritual vessel because of its "divine" characteristics.

In the ancient culture of China, the History of Five Elements said that the rainbow was "the weather around the sun", but it was close to the understanding of modern knowledge. But the mainstream concept still regards it as the existence of supernatural power for a long time. Rainbow is generally considered as a god with two heads that can drink water.

In addition, 396 volumes of Taiping Guang Ji also recorded some short stories about rainbows. For example, in Xue Yuan, it is recorded that a rainbow reached into Xue Yuan's pot to drink water. After a loud noise, it sucked up the water. Xue yuan poured wine into it again, and the result was that it drained while pouring.

Zhuzi Genre records Zhuzi's view that the rainbow "can not only sip water, but also have a stomach". In Zhuzi's understanding, rainbows that can drink water have stomachs like other creatures. Zulu people in southern Africa, ancient Mayans in Central America and Karen people in Myanmar also say that rainbows can drink water. The widespread spread of this concept may be because rainbows often appear in wells, lakes, streams and other places after rain, which seems to the ancients to be drinking water.