In this theory, "using God" refers to the most important element in a person's fate, representing a person's talent, strengths and weaknesses. If a person's use of god is wood, then his fate lacks the element of wood, and more wood is needed to give play to his talents and advantages.
XiShen, on the other hand, refers to the favorite elements in one's destiny, which represents one's preferences, hobbies and interests. If a person's western god is earth, then he likes the element of earth in his destiny, even if there is no earth, it doesn't matter, but with more earth, he can give full play to his talents and abilities.
Generally speaking, the saying that "God is wood and XiShen is earth" shows that a person's fate needs to balance the five elements in order to reach the best state. At the same time, we should also choose a career and lifestyle that suits our needs according to our situation of using God and XiShen.