Num 12:1-16
When they were in Hazeroth, Miriam and Aaron spoke against Moses because of the Cushite woman he had married: “He married a Cushite woman!” They said, “Has the LORD spoken only through Moses? Has He not spoken through us as well?” The LORD heard it. Now Moses was a very humble man, more so than any other man on earth. Suddenly the LORD called to Moses, Aaron, and Miriam, “Come out, you three, to the Tent of Meeting.” So the three of them went out. The LORD came down in a pillar of cloud, stopped at the entrance of the Tent, and called out, “Aaron and Miriam!” The two of them came forward; and He said, “Hear these My words: When a prophet of the LORD arises among you, I make Myself known to him in a vision, I speak with him in a dream. Not so with My servant Moses; he is trusted throughout My household. With him I speak mouth to mouth, plainly and not in riddles, and he beholds the likeness of the LORD. How then did you not shrink from speaking against My servant Moses!” Still incensed with them, the LORD departed. As the cloud withdrew from the Tent, there was Miriam stricken with snow-white scales! When Aaron turned toward Miriam, he saw that she was stricken with scales. And Aaron said to Moses, “O my lord, account not to us the sin which we committed in our folly. Let her not be as one dead, who emerges from his mother’s womb with half his flesh eaten away. ”So Moses cried out to the LORD, saying, “O God, pray heal her!” But the LORD said to Moses, “If her father spat in her face, would she not bear her shame for seven days? Let her be shut out of camp for seven days, and then let her be readmitted.” So Miriam was shut out of camp seven days; and the people did not march on until Miriam was readmitted. After that the people set out from Hazeroth and encamped in the wilderness of Paran.
Midrash
The meaning of Cushite is uncertain; it may refer to the African country of Cush (Ethiopia), or to a portion of Midian, from which Zipporah (named as Moses’ wife) came.
Although the Torah passage clearly states that Both Aaron and Miriam spoke against Moses and that God’s words were directed toward both of them, only Miriam was punished. The Rabbis attempt to explain this disparity by saying that Miriam initiated the conversation or that the cloak of the High Priest protected Aaron from punishment [Sifrei Zuda 12:9]. In another Midrash, Miriam received special treatment in her affliction. Since Aaron as a kohen typically would care for Miriam, he could not in this case since he was related to Miriam. Instead, God himself cared for Miriam [Lev. Rabbah 15:8; Zevahim 102a].
Various Midrashim explain why the people waited for Miriam during her seven day confinement before continuing their journey (signifying her importance within the community). One Midrash views this as Miriam’s reward for waiting for Moses’ rescue at the riverbank [Mishnah Sotah 1:9]; a second claims that the some of the Israelites wanted to continue but faced various natural impediments [Mishnah Yelamdenu; Sifrei Bamidbar 106].