Writing notes is significant as in this way one can have his Torah last even after he dies. In this manner we can grasp כתב זאת זכרון בספר, write a sefer so that it lives beyond you.
In his magnum opus, the Mabit writes, “Therefore every person who has a new Torah insight has a duty to impart what he derived with his wisdom. And if Hashem bestows upon them the merit to make Torah great and glorious, he should also write it and, in turn, share it with those far and near so that they will all benefit from his intellect. In this manner, he will leave behind an eternal blessing as they study his written works.”
The Steipler writes, “One must write down all his Chidushei Torah. I am aware of numerous scholars who dedicated their lives to diligent study, yet sadly, the next generation did not have access to any of their Torah study. This omission occurred solely because they did not write and publish their Divrei Torah.”
The Steipler would often convey to R' Chaim Kanievsky the unfortunate consequence for both the Torah scholar himself and future generations if his Torah is not written down.
We only know the Maharsha, the Rosh, and many others because of their sefarim. How much would we be lacking if we didn’t have their sefarim! Similarly, people today should think about how their Torah will be remembered after they pass away. Today we even have machines to record shiurim, which can also ensure that one’s Torah not be lost after death. R’ Avigdor Miller was conscious of this and thus recorded his shiurim on a tape recorder. Because of this we have a multitude of sefarim from him, as some of his sefarim were based on those recordings. Of course one’s Torah can also live on in the people to whom he gives shiurim during his lifetime, particularly when they integrate the Torah that was taught. And many rabbanim have had students who wrote up their Torah after they died.
