Answer: According to Baal HaSulam in the Introduction to The Study of the Ten Sefirot and the Vilna Gaon in the Sidur of the HAGRA, it is impossible to attain the Torah without understanding its four layers.
The sages who wrote the Torah and all the holy books wrote them from the level on which they attained every part of reality and the corporeal reality, which is revealed to us. This is the reason that I want to learn from what they revealed in the Torah and not to settle for mechanical actions.
I cannot understand what the Torah says and what the sages wanted to convey if I don’t understand the internal meaning of the Torah. I am like a kid who doesn’t know how to read but only leafs through a book looking at the pictures.