Torah study can elevate a person to great heights, but if he is unworthy and studies the Torah improperly, it can bring him down to the lowest depths.

Rabbi Yehoshua ben Levi said: What is the meaning of what is written: “And this is the Torah that Moses placed [sam] before the children of Israel” (Deuteronomy 4:44)? If one is worthy, the Torah becomes a potion [sam] of life for him; if one is not worthy, the Torah becomes a potion of death for him. This is what Rava said: For one who studies Torah for its own sake, it is a potion of life; but for one who studies Torah not for its own sake, it is a potion of death.

Rabbi Shmuel bar Nahmani said that Rabbi Yonatan raised a contradiction: It is written: “The precepts of the Lord are upright, gladdening the heart” (Psalms 9:19), and it is written: “The word of the Lord is refining” (Psalms 18:31). He resolves the contradiction: For one who is worthy, the Torah gladdens him; for one who is not worthy, it refines him.

The Sages taught: There are three types of people over whom the Holy One, blessed be He, cries every day: one who is able to engage in Torah study and does not engage in it; one who is unable to engage in Torah study but engages in it; and a leader who is domineering over the community. (Yoma 72b; Ĥagiga 5b)