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.
