Vilna Gaon - Torah can bring you up or bring you down

Question

Does anyone know the source of the Vilna Gaon talking about Torah and saying that it can either be used for the good or for the bad, it depends on one’s midot. He said that Torah is like rain. If you have good midot (a good seed) and learn Torah then it is constructive. But if you have bad midot and learn Torah it will be even more destructive because Torah learning on its own has power, and whichever way you lead it that’s where you go. So therefore one should put heavy focus on his midot to make sure when he learns Torah he builds something constructive and not the opposite chas

Answer 1

This teaching of the Vilna Gaon is quoted in Even Sheleimah #47:

ענין התורה לנפש דוגמת המטר לארץ שמצמיח מה שנזרע בה סם חיים או סם מות. כן בתורה מצמיח מה שבלבו אם לבו טוב תגדיל יראתו. ואם בלבו שורש פורה ראש ולענה יגדיל הטינא בלבו ... ע"כ צריך לפנות לבו בכל יום קודם הלימוד ואחריו מעיפוש הדיעות והמדות ביראת חטא ומע"ט

The Torah's effect on the soul is like that of rain on the ground, in that it causes whatever is planted there to grow, whether good or bad. So too, the Torah causes whatever is in a person's heart to grow. If he is good-hearted, the Torah will increase his piety. But if his heart contains the seeds of bad behavior, the bitterness in his heart will only increase ... Therefore, every day, before and after learning, one has to cleanse his heart from poor behaviors, with increased piety and good deeds.

(my own fairly free translation)

As noted in the reference there, this is based on a number of passages in the Gaon's commentary to Mishlei, primarily Mishlei 24:31.