The first aliyah discusses laws of verbal vows by means of which someone obligates himself or herself with a vow. Such a person must do all that he vows. Then the aliyah gives the laws of a woman who makes a vow and how her husband or father, under certain circumstances, can overturn such vows.

The Torah continues with G-d commanding Moshe to take revenge against the Midianites, after which time Moshe shall pass away. This aliyah describes the war taking place with an army of 12,000 Jews. All adult males of Midian as well as their five Kings are killed in this battle. The non-Jewish prophet Bilam, who was the main subject of parsha Balak that we read two weeks ago, dies in this war.

The second aliyah discusses the purification of the soldiers and the spoils of war from contact with the dead.

The aliyah continues with the spoils of the war with Midian being divided equally between the soldiers and the community. From the half of the spoils of war going to the soldiers, 1/500 is given to Elazar the priest as an offering to G-d. From the other half, which is for the community, 1/50 is given to the Levites.

The officers of the army did a census of the soldiers and determined that not a single man was lost in the war and therefore they, the officers, gave a special offering to G-d.

The third aliyah begins by stating that the tribes of Reuvein and Gad have a lot of cattle. They see that the side of the Jordan that they are on now, before crossing the Jordan River into Israel, is an ideal place for so much cattle. They therefore ask Moshe if they can have their inheritance outside of Israel, on this side of the Jordan. Moshe answers them that this is like the matter of the spies, in that their not wanting to go into the land of Israel will discourage everyone else from wanting to proceed into the land. They reply to Moshe that they will leave their cattle and families here, but their men will go with the other Jews into Israel and conquer it with them. And only after all the rest of the Jews inherit their land, they will return to this side of the Jordan.

In the fourth aliyah, Moshe accepts the offer of the tribes of Reuvein and Gad to go to battle for the land of Israel with the rest of the Jews, after which they will return and inherit land on this side of the Jordan. So in this aliyah these tribes are given land for the families and cattle to be safeguarded while they go across the Jordan with everyone else.