The allusions of the four letters of Yud Hei Vav Hei
Synopsis
We learn from Rabbi Yehuda that the firmament that divided between the upper and lower waters is the reason that there is peace between them; the world is established upon peace, and God's name is peace. Rabbi Aba talks about the letters in the name of God, Yud Hei Vav Hei, and concludes by saying that the Yud is the essence and root and perfection of everything.