This first aliyah gives instructions that a completely red cow (the para duma) is to be slaughtered, and burnt, and its ashes saved. Then, when a person becomes tamai mais (impurity from a dead body), a procedure is described here where such a person is purified on the third and seventh day with the ashes of the para duma, and after that, he is tahar (pure).

The interesting thing is that the ashes of the red heifer can make someone pure, but all the people involved in the manufacture and use of the ashes become impure from their involvement. This is why this is considered the biggest chok of them all.

This aliyah then brings the story of the Jews' travels 38 years later to the 40th year in the desert, when the Jews stopped in the wilderness of Tzin. It is here that Miriam, who was Moshe and Aharon's sister, passes away and is buried. Immediately after this, the Torah says the people had no water, and Rashi says that this is an indication that previous to Miriam's death, for 40 years, the Jewish community had plenty of water from a well provided because of Miriam's righteousness. The people start bitterly complaining about the lack of water to Moshe and Aharon.