All the tzaddikim in each generation are holy and have God with them. Why then do we see that while some tzaddikim are very good-natured and well-liked by everyone, there is a true tzaddik who by temperament and nature is not amiable with people, and who sometimes even displays much anger and irritability?

Now, it is known that the tzaddikim derive all their righteousness from the light of the Torah. She is his guide, and he gets his righteousness from her. When a tzaddik has attained great illumination from the Torah’s light, and his good deeds are exactly on a par with his perception of Torah, then his righteousness and Torah are in amicable accord with each other. He therefore gets along with people.

But when a tzaddik’s perception of the Torah’s wisdom greatly surpasses his deeds, the Torah boils inside him—that is, the great, holy fire of the Torah burns inside him. Thus, it is impossible for him to get along with others and be involved with people, similar to the aforementioned tzaddik.

This is as our Sages, of blessed memory, taught: When a young rabbinical student becomes heated, it is the Torah that is causing him to become heated (Taanit 4a). This is because his Torah has increased greatly, as explained above.