What did the ancients mean by "three cleanses in one breath"?

As soon as the old gentleman in Taishang vaporized, he carried out three purges, (Jade Qing Xiaotian Buddha in the early Yuan Dynasty, Yu Yu Lingbao Buddha, and Taiqing Moral Buddha in the late Qing Dynasty).

"One gasification and three cleannesses" first came from Xu's "Romance of the Gods", which tells the story that when the old gentleman in Taishang fights with Tianshi, he makes three dharma bodies with one gasification. Taoist Sanqing originally refers to the three gods of Jade Qing, Shangqing and Taiqing, which are collectively called Taiqing moral gods, also referred to as Taishang Laojun. It is the earliest highest god worshipped by Taoism, or incarnated as Laozi. Later, due to the theory of "one gasification and three cleanness", one god changed into three gods, and the old gentleman in Taishang was listed as three gods. Lao Tzu is an old man, too. "Seven Stars Cloud" is also used to write about the emergence of Sanqing. "The original Daoism began in Zhao, from scratch, and the trace can be felt. It was divided into three elements, and then changed from three elements to three gases ... the first mixed hole space, the second mixed red space, and the third ghost was silent and mysterious. From the mixed point, there is no element to give birth to Tianbaojun, from the red mixed point, there is no element to give birth to Lingbaojun, and from the mysterious Xuanyuan to give birth to Shenbaojun. " Since the three elements have become three qi and three gods, these three gods are naturally the embodiment of three qi. These three gods were actually called Sanqing gods in later generations. Therefore, there is a saying in later generations that "one breath and three cleanses", which shows that "qi" is the basic element of building the highest Taoist god. Similarly, the immortals under the Supreme God are also composed of "Qi". For example, "The Jade Emperor is the transformation of Sanqing in Taoism." That is, the ancestral spirit of Sanqing changed. "Five old gods are the root of five qi, and the five elements are the foundation." It shows that the "qi" of the jade emperor and the five old gentlemen comes directly from the root Sect.