All aspects of Torah are deep and profound. These is absolutely nothing superficial in the Torah, G-d forbid. Everything contained in the Torah is deep and vast, and to learn any aspect of it correctly, on must study in-depth. While most agree that learning Talmud or Halakah require in-depth study, many consider the avoda (self-work) of correcting our midot (character traits) to require only minimal effort.
Hashem gave us the Torah, and our soul is the the “vessel” for receiving the light of the Torah and its mitzvot. When we learn Torah, the Torah should become a part of us. Before we learn, we say that the Torah is “available in the corner” (Kiddushin 66a). However, once we toil to understand the Torah to the best of our ability, it is call “his Torah” (ibid 32b). In this way, the Torah we toil to learn goes from being “in the corner” to being “Your Torah is inside of me” (T’hillim 40:9).
The Torah and mitzvot are like water, as in, “All who are thirsty come to the water” (Isaiah 55:1). The vessel to receive the Torah is the actual individual who learns and fulfills it. This is why it is important for us to work on ourselves in order to become a pure vessel to hold the light of the Torah we learn, the “water” of Torah. If the vessel is pure and holy, the water of Torah we learn will be pure and holy.
However, if we remain tainted, which is our natural starting point, as in, “the inclination of a person is evil from one’s youth” (Genesis 8:21), the light of the Torah will not shine in us. It is through the avoda (self-work) of improving our midot and behavior that we rectify our own vessel that maintains holiness.
Based on Bilvavi On the Path: The Ramchal’s Introduction and Chapter One, by the author of Bilvavi Mishkan Evneh