There is a widespread custom in many communities to learn Torah the entire first night of Shavuot until Shacharit. This practice is not mentioned in the Shulchan Aruch but is brought down by the Mishnah Berurah (Hilchot Shavuot 494:1), who quotes the Zohar as saying that pious people would stay up the entire first night of Shavuot and learn Torah. In fact, the Zohar brings down that anybody who learns the entire first night of Shavuot will be protected from all harm in the following year.
Although this custom began with small groups of intense Torah scholars, the practice has grown and become prevalent in many communities. Why is it so important to stay up all night learning Torah on the holiday of Shavuot?
The Midrash on Parashat Yitro (Shemot 19:17) writes that Bnei Yisrael overslept on the morning of Mattan Torah and had to be woken by Moshe Rabbeinu. The Magen Avraham explains that we learn all night and do not go to sleep in order to rectify Bnei Yisrael’s mistake of oversleeping.
It is difficult to understand how Bnei Yisrael overslept on this extremely important morning. Rabbi Yisrael of Koznitz (the Maggid of Koznitz) cites the opinion of Rav Levi Yitzchak of Berditchev that Bnei Yisrael overslept because they were tired from their extensive preparation for Mattan Torah. They were concerned about accepting the Torah in such an exhausted state, so they went to sleep that night in order to accept the Torah refreshed with focus and excitement.
The Maggid of Koznitz’s answer puts a positive spin on the seemingly horrible act of oversleeping on the day of Mattan Torah. This opinion fits in with our general feeling that the generation of Bnei Yisrael at Mattan Torah was the holiest to ever exist. This notion is supported by the Gemara (Berachot 5b), which teaches us that when Bnei Yisrael traveled from Refidim to Har Sinai, they left a state of laxity towards Avodat Hashem and entered into a state of serious Avodat Hashem and unity. This Gemara clearly confirms the fact that Bnei Yisrael approached Mattan Torah with the best intentions.
May our forefathers’ attitudes and feelings at Mattan Torah serve as an example to us as we learn Torah this Shavuot, whether throughout the night or not, and help us prepare for our individual Kabbalat HaTorah, with dedication, focus, and excitement.