Tikkun Leil Shavuot is said to have been officially established by the famous 16th-century kabbalist, Rabbi Isaac Luria, more commonly referred to as the Arizal or the Ari. However, there are references to the custom in the Zohar, which first emerged in the 13th century but is said to have actually been written by Rabbi Shimon Bar Yochai, a Second Temple sage.
Shavuot celebrates the giving of the Torah by God to the Jewish people, but, according to the Midrash, the Children of Israel overslept on the morning they were due to receive the Torah, and had to be woken by a shofar blast from God.
Tikkun means “correction”, while “Leil Shavuot” means “night of Shavuot.” As a correction for having overslept, the Ari initiated the custom of all-night learning. Rather than sleeping late, Jews would not sleep at all.
But the custom appears to go back far earlier. According to one version of the Zohar, talking about the night of Shavuot, it says:
“We learned that the Torah we must labour in on this night is the Oral Law, so that together we are purified from the deep wellspring of the stream.
“Because of this, the early Chasidim [pious ones] did not sleep that night and toiled in Torah.”
Many synagogues offer Tikkun Leil Shavuot learning programmes, with Torah classes or talks.
While there is no requirement to learn something specific, there is a special text for Tikkun Leil Shavuot, which some people recite. It contains excerpts from all 54 Sidrot (the sections which the Chumash is split into), as well as excerpts from the books of the Prophets, and Midrashim. There are also a number of Piyutim (special prayers), which can be recited on the night of Shavuot.