The Rav has said that the main kind of Torah learning is to learn in order to know how to fulfill all of the mitzvos, and that besides for this, one also needs to learn certain parts of Torah which are aligned with his personal soul root (shoresh haneshamah). The Rav has said that we see this from the face that there were some Gedolim did not learn Kaballah (the mystical secrets of the Torah) [for this part of Torah was not needed according to their personal shoresh haneshamah]. The Rav referred me to the words of the Shulchan Aruch HaRav in Hilchos Talmud Torah (1:4) who writes, “The Sages of truth said that every soul, in order to reach its tikkun (repair), needs to study the PaRDeS (the four parts of Torah, which includes Pshat [surface understanding], Remez [hints, gematria, etc.], Drush [homiletics, agadta, etc.] and Sod [the mystical parts of Torah, the Kaballah, etc.] according to one’s capability of comprehension. One needs to know all of it, and this is the complete tikkun (repair) for the soul.” From those words it is apparent that each person needs to study all of the PaRDes, and it is just that he is only required to do so according to his level of comprehension – and it seems that vice versa, if a person is not able to known and comprehend all of PaRDeS, then he is not obligated to know all of PaRDes.
But how can a person know what the capabilities of his soul are, when it comes to learning all of the parts of Torah? How can a person know how much he can or cannot understand in the Torah? If one spends time learning a certain part of Torah in favor of other parts, maybe this is stemming from laziness, even if he’s exerting himself to understand what he’s trying to understand. After having this question I later came across a statement in the name of the kaballists that the colleagues of Rabbi Akiva rebuked Rabbi Akiva for learning matters of agadta and told him that he should instead learn the laws of negaim and ohalos, and this was because they looked into the soul of Rabbi Akiva and saw that his main share in Torah was in halachah [specifically, of negaim and ohalos] as opposed to agadta. The kaballists then cite the words of the Arizal that each person needs to learn the areas of Torah that are according to his personal soul root. This is brought in sefer Shaalos U’Teshuvos Rav Pealim: Yoreh Deah 1:56). It seems from this that even Rabbi Akiva didn’t know his personal root and what his personal share in Torah should be, until they told him.
So, the question is: Nowadays, who can tell a person what kind of neshamah (soul) he has?
The very pnimiyus (inner essence) of our neshamah is at first hidden from a person, due to internal “bribery” – various self-serving interests (retzonos). When one nullifies these retzonos, he reaches hishtavus (equality), and then he can know what his personal share is, in which area of Torah learning he should be spending his exertion on.