On the night before the circumcision will be performed, young children come to the home of the newborn baby and recite Torah verses.
This night is called vacht nacht in Yiddish, "night of watching." The corresponding tradition in Sephardic communities is referred to as Brit Yitzchak, "Covenant of Isaac."
There is also an ancient custom that someone in the home remain awake the entire night—or at least until midnight (click here to see when that is)—studying Jewish texts, including a specific excerpt from the Zohar, the classic work of Kabbalah compiled by the 2nd-century great sage Rabbi Shimon bar Yochai.
Some families host a feast in their home on this night, where those who will take an active part in the ritual ceremony join together to rejoice and honor this great Divine commandment. Some families invite their friends as well.
The act of ritual circumcision is the greatest act known to the Jewish nation, an enactment of the powerful physical bond between G‑d and Jew. Whenever a force comes to shift the world in a positive direction, opposite forces come into play. Our tradition tells us that words of Torah, especially coming from children, are capable of breaking that equilibrium and allowing true transformation to take place.