Tazria: Chapter 15
"The earth is Hashem's, and the fullness thereof"
Synopsis

Rabbi Yosi says that, since the day the Temple was destroyed, we are not allowed to look at joyful things. The rabbis discuss the title verse, and they learn from Rabbi Shimon that all the Mochin come from the supernal river that flows out of Eden, and Malchut is established by them so that it can nourish the worlds. The main theme is that the world depends on righteousness.