Divine Tao has two types of cultivation, one for Divine Spirit Cultivators and another for Witchcraft.
The Original Dao Salvation Song is the unique cultivation method of the Holy Infant Sect, positioned between Divine Spirit and Witchcraft, and it's called the "Divine Son Cultivation Method." Once perfected, if the cultivator dies, their Divine Soul automatically merges with the Divine Spirit, remaining in the world eternally. The Three Weis Discipline, for instance, is purely Witchcraft, used to establish a connection between the cultivator and the Divine Spirit. As for how high one can achieve, it depends on the Divine Spirit's will.
Du Bin knew that Wang Qi had ambitious plans, but hadn't expected him to be so suicidal.
What is the Holy Infant Sect? It's the foremost Divine sect of eternity. And what is a Divine sect? It is the very entity that the Immortal Alliance swore to eradicate!