What does Lao Tzu mean by turning Hu into a Buddha in Hanguguan?

This means that after I went west to Hanguguan, I transformed the Hu people into Buddhas. This is how Taoism suppresses Buddhism. Before the Yuan Dynasty, there was a classic "Opening Classics of Taishang Laojun". But later the argument failed, proving that the folio was forged. Since then, there has been no folio in Taoist classics.

1 is the most important and basic viewpoint of Laozi Hu Jing, and it is also the cornerstone of Taoist thought. The Taoist scriptures say, "Laozi is me and I am Laozi", which is in the same strain as Taoist thought. "Three Zhang" put forward the ideas of "I am Tao" and "I am Laozi" in the early stage, and put forward the ideas of "I am Tathagata" and "I am Sakyamuni" in the later stage, which added new contents to Taoism.

2. Expressed the firm belief that early Taoist priests should always be in the forefront of the times and be leaders of the times, which had a great and far-reaching impact on the development of Taoism in China and Buddhism in China.

Extended data:

Lao Zi's Real Intention of Turning Hu into Buddha

Laozi taught the world to choose different methods according to the root causes. At that time, the Hu people were barbaric, greedy, lazy, shallow-rooted and ignorant of Taoism, so Lao Tzu taught Sakyamuni pagoda method, just as dogs had to eat dog food to be healthier. Only by practicing Buddhism can Hu people eliminate their barbaric nature.

Taoism and Buddhism have also been fighting in the dark. Although both of them are merciful, they must strive for the development of this religion. The ancients in China didn't know the origin of foreign Buddhism, but Taoism just took advantage of this, saying that Buddhism was founded by Laozi, the founder of Taoism, in order to enhance the status of Taoism. So Lao Tzu said, "Turn Hu into Buddha".

Baidu Encyclopedia-Old Zi Hua Hu Jing